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Square Root PropertyIfx2=kx2=k, andk≥0k≥0, thenx=korx=−kx=korx=−k.
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Binomial Squares Pattern Ifa,ba,bare real numbers,(a+b)2=a2+2ab+b2(a+b)2=a2+2ab+b2(a−b)2=a2−2ab+b2(a−b)2=a2−2ab+b2
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Complete a SquareTo complete the square ofx2+bxx2+bx:Step 1.Identifybb, the coefficient ofxx.Step 2.Find(12b)2(12b)2, the number to complete the square.Step 3.Add the(12b)2(12b)2tox2+bxx2+bx.
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Step 1.Identifybb, the coefficient ofxx.
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Step 2.Find(12b)2(12b)2, the number to complete the square.
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Step 3.Add the(12b)2(12b)2tox2+bxx2+bx.
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Quadratic FormulaThe solutions to a quadratic equation of the formax2+bx+c=0,ax2+bx+c=0,aâ‰0aâ‰0are given by the formula:x=−b±b2−4ac2ax=−b±b2−4ac2a
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Solve a Quadratic Equation Using the Quadratic FormulaTo solve a quadratic equation using the Quadratic Formula.Step 1.Write the quadratic formula in standard form. Identify thea,b,ca,b,cvalues.Step 2.Write the quadratic formula. Then substitute in the values ofa,b,c.a,b,c.Step 3.Simplify.Step 4.Check the solutions.
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Step 1.Write the quadratic formula in standard form. Identify thea,b,ca,b,cvalues.
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Step 2.Write the quadratic formula. Then substitute in the values ofa,b,c.a,b,c.
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Step 3.Simplify.
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Step 4.Check the solutions.
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Using the Discriminant,b2−4acb2−4ac, to Determine the Number of Solutions of a Quadratic EquationFor a quadratic equation of the formax2+bx+c=0,ax2+bx+c=0,aâ‰0,aâ‰0,ifb2−4ac>0b2−4ac>0, the equation has 2 solutions.ifb2−4ac=0b2−4ac=0, the equation has 1 solution.ifb2−4ac<0b2−4ac<0, the equation has no re...
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ifb2−4ac>0b2−4ac>0, the equation has 2 solutions.
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ifb2−4ac=0b2−4ac=0, the equation has 1 solution.
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ifb2−4ac<0b2−4ac<0, the equation has no real solutions.
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To identify the most appropriate method to solve a quadratic equation:Step 1.Try Factoring first. If the quadratic factors easily this method is very quick.Step 2.Try the Square Root Property next. If the equation fits the formax2=kax2=kora(x−h)2=ka(x−h)2=k, it can easily be solved by using the Square Root Property...
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Step 1.Try Factoring first. If the quadratic factors easily this method is very quick.
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Step 2.Try the Square Root Property next. If the equation fits the formax2=kax2=kora(x−h)2=ka(x−h)2=k, it can easily be solved by using the Square Root Property.
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Step 3.Use the Quadratic Formula. Any other quadratic equation is best solved by using the Quadratic Formula.
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Area of a TriangleFor a triangle with base,bb, and height,hh, the area,AA, is given by the formula:A=12bhA=12bh
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Pythagorean TheoremIn any right triangle, whereaaandbbare the lengths of the legs, andccis the length of the hypothenuse,a2+b2=c2a2+b2=c2
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Projectile motionThe height in feet,hh, of an object shot upwards into the air with initial velocity,v0v0, afterttseconds can be modeled by the formula:h=−16t2+v0th=−16t2+v0t
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The graph of every quadratic equation is a parabola.
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Parabola OrientationFor the quadratic equationy=ax2+bx+cy=ax2+bx+c, ifa>0a>0, the parabola opens upward.a<0a<0, the parabola opens downward.
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a>0a>0, the parabola opens upward.
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a<0a<0, the parabola opens downward.
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Axis of Symmetry and Vertex of a ParabolaFor a parabola with equationy=ax2+bx+cy=ax2+bx+c:The axis of symmetry of a parabola is the linex=−b2ax=−b2a.The vertex is on the axis of symmetry, so itsx-coordinate is−b2a−b2a.To find they-coordinate of the vertex we substitutex=−b2ax=−b2ainto the quadratic equation...
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The axis of symmetry of a parabola is the linex=−b2ax=−b2a.
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The vertex is on the axis of symmetry, so itsx-coordinate is−b2a−b2a.
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To find they-coordinate of the vertex we substitutex=−b2ax=−b2ainto the quadratic equation.
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Find the Intercepts of a ParabolaTo find the intercepts of a parabola with equationy=ax2+bx+cy=ax2+bx+c:y-interceptx-interceptsLetx=0and solve fory.Lety=0and solve forx.y-interceptx-interceptsLetx=0and solve fory.Lety=0and solve forx.
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To Graph a Quadratic Equation in Two VariablesStep 1.Write the quadratic equation withyyon one side.Step 2.Determine whether the parabola opens upward or downward.Step 3.Find the axis of symmetry.Step 4.Find the vertex.Step 5.Find they-intercept. Find the point symmetric to they-intercept across the axis of symmetry.St...
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Step 1.Write the quadratic equation withyyon one side.
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Step 2.Determine whether the parabola opens upward or downward.
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Step 3.Find the axis of symmetry.
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Step 4.Find the vertex.
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Step 5.Find they-intercept. Find the point symmetric to they-intercept across the axis of symmetry.
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Step 6.Find thex-intercepts.
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Step 7.Graph the parabola.
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Minimum or Maximum Values of a Quadratic EquationThey-coordinate of the vertexof the graph of a quadratic equation is theminimumvalue of the quadratic equation if the parabola opens upward.maximumvalue of the quadratic equation if the parabola opens downward.
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They-coordinate of the vertexof the graph of a quadratic equation is the
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minimumvalue of the quadratic equation if the parabola opens upward.
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maximumvalue of the quadratic equation if the parabola opens downward.
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axis of symmetry : The axis of symmetry is the vertical line passing through the middle of the parabolay=ax2+bx+c.y=ax2+bx+c.
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completing the square : Completing the square is a method used to solve quadratic equations.
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consecutive even integers : Consecutive even integers are even integers that follow right after one another. If an even integer is represented bynn, the next consecutive even integer isn+2n+2, and the next after that isn+4n+4.
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consecutive odd integers : Consecutive odd integers are odd integers that follow right after one another. If an odd integer is represented bynn, the next consecutive odd integer isn+2n+2, and the next after that isn+4n+4.
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discriminant : In the Quadratic Formula,x=−b±b2−4ac2ax=−b±b2−4ac2athe quantityb2−4acb2−4acis called the discriminant.
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parabola : The graph of a quadratic equation in two variables is a parabola.
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quadratic equation : A quadratic equation is an equation of the formax2+bx+c=0ax2+bx+c=0, whereaâ‰0.aâ‰0.
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quadratic equation in two variables : A quadratic equation in two variables, wherea,b,andca,b,andcare real numbers andaâ‰0aâ‰0is an equation of the formy=ax2+bx+c.y=ax2+bx+c.
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Square Root Property : The Square Root Property states that, ifx2=kx2=kandk≥0k≥0, thenx=korx=−k.x=korx=−k.
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vertex : The point on the parabola that is on the axis of symmetry is called thevertexof the parabola; it is the lowest or highest point on the parabola, depending on whether the parabola opens upwards or downwards.
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x-intercepts of a parabola : Thex-intercepts are the points on the parabola wherey=0.y=0.
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y-intercept of a parabola : They-intercept is the point on the parabola wherex=0.x=0.
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a + b a + b
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a ÷ b , a / b , a b , b a a ÷ b , a / b , a b , b a
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Commutative Property When adding or multiplying, changing the order gives the same result of addition If a , b are real numbers, then a + b = b + a of multiplication If a , b are real numbers, then a · b = b · a of addition If a , b are real numbers, then a + b = b + a of multiplication If a , b are real numbers, the...
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Associative Property When adding or multiplying, changing the grouping gives the same result. of addition If a , b , and c are real numbers, then ( a + b ) + c = a + ( b + c ) of multiplication If a , b , and c are real numbers, then ( a · b ) · c = a · ( b · c ) of addition If a , b , and c are real numbers, then ...
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Distributive Property If a , b , and c are real numbers, then a ( b + c ) = a b + a c ( b + c ) a = b a + c a a ( b − c ) = a b − a c ( b − c ) a = b a − c a If a , b , and c are real numbers, then a ( b + c ) = a b + a c ( b + c ) a = b a + c a a ( b − c ) = a b − a c ( b − c ) a = b a − c a
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Identity Property of addition For any real number a : a + 0 = a 0 is the additive identity 0 + a = a of multiplication For any real number a : a · 1 = a 1 is the multiplicative identity 1 · a = a of addition For any real number a : a + 0 = a 0 is the additive identity 0 + a = a of multiplication For any real number a...
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Inverse Property of addition For any real number a , a + ( − a ) = 0 − a is the additive inverse of a A number and its o p p o s i t e add to zero. of multiplication For any real number a , a ≠0 a · 1 a = 1 1 a is the multiplicative inverse of a A number and its r e c i p r o c a l multiply to one. of addition F...
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Properties of Zero For any real number a , a · 0 = 0 0 · a = 0 For any real number a , a ≠0 , 0 a = 0 For any real number a , a 0 is undefined For any real number a , a · 0 = 0 0 · a = 0 For any real number a , a ≠0 , 0 a = 0 For any real number a , a 0 is undefined
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absolute value : The absolute value of a number is its distance from00on the number line.
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additive identity : The number 0 is the additive identity because adding 0 to any number does not change its value.
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additive inverse : The opposite of a number is its additive inverse.
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coefficient : The coefficient of a term is the constant that multiplies the variable in a term.
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complex fraction : A fraction in which the numerator or the denominator is a fraction is called a complex fraction.
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composite number : A composite number is a counting number that is not prime. It has factors other than 1 and the number itself.
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constant : A constant is a number whose value always stays the same.
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denominator : In a fraction, writtenab,ab,wherebâ‰0,bâ‰0,the denominatorbis the number of equal parts the whole has been divided into.
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divisible by a number : If a numbermis a multiple ofn, thenmis divisible byn.
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equation : An equation is two expressions connected by an equal sign.
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equivalent fractions : Equivalent fractions are fractions that have the same value.
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evaluate an expression : To evaluate an expression means to find the value of the expression when the variables are replaced by given numbers.
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expression : An expression is a number, a variable, or a combination of numbers and variables using operation symbols.
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factors : Ifa·b=m,a·b=m,thenaandbare factors ofm.
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fraction : A fraction is writtenab,ab,wherebâ‰0,bâ‰0,andais the numerator andbis the denominator. A fraction represents parts of a whole.
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integers : The whole numbers and their opposites are called the integers.
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irrational number : An irrational number is a number that cannot be written as the ratio of two integers. Its decimal form does not stop and does not repeat.
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least common denominator : The least common denominator (LCD) of two fractions is the least common multiple (LCM) of their denominators.
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least common multiple : The least common multiple (LCM) of two numbers is the smallest number that is a multiple of both numbers.
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like terms : Terms that are either constants or have the same variables raised to the same powers are called like terms.
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multiple of a number : A number is a multiple ofnif it is the product of a counting number andn.
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multiplicative identity : The number 1 is the multiplicative identity because multiplying 1 by any number does not change its value.
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multiplicative inverse : The reciprocal of a number is its multiplicative inverse.
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negative numbers : Numbers less than00are negative numbers.
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numerator : In a fraction, writtenab,ab,wherebâ‰0,bâ‰0,the numeratoraindicates how many parts are included.
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opposite : The opposite of a number is the number that is the same distance from zero on the number line but on the opposite side of zero.
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order of operations : The order of operations are established guidelines for simplifying an expression.
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percent : A percent is a ratio whose denominator is 100.
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prime factorization : The prime factorization of a number is the product of prime numbers that equals the number.
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prime number : A prime number is a counting number greater than 1 whose only factors are 1 and the number itself.
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principal square root : The positive square root is called the principal square root.
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rational number : A rational number is a number of the formpq,pq,wherepandqare integers andqâ‰0.qâ‰0.Its decimal form stops or repeats.
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real number : A real number is a number that is either rational or irrational.
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reciprocal : The reciprocal of a fraction is found by inverting the fraction, placing the numerator in the denominator and the denominator in the numerator.
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simplify an expression : To simplify an expression means to do all the math possible.
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square of a number : Ifn2=m,n2=m,thenmis the square ofn.
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