| --- |
| source: ncert |
| topic: algebra |
| class_level: class_6 |
| chapter: ch11 |
| difficulty: beginner |
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| |
| Class 6 | Ch11: Algebra - Introduction |
| Variable: letter for unknown (x,y,n). Constant: fixed value. |
| 3x means 3×x. x^2 means x×x. "5 less than x" = x-5 NOT 5-x. |
| Like terms: same variable and power (3x and 7x). Unlike: different. |
| Expression: no equal sign (2x+3). Equation: has equal sign (2x+3=11). |
| Substitution: x=4 in 3x+5 = 3(4)+5=17. |
| "5 added to 3 times x"=3x+5. "y subtracted from 10"=10-y. |
| "Twice a number decreased by 4"=2n-4. |
| An expression has no solution. Only equations can be solved. |
