Question

1. Simplify combining like terms :
(1) 42a-52 +8a-15b

(ii) a-(a−b)-b-(2b-a)

(iii) (5x2 +6x – 3)–(4x –2x -8)

(iv) 2x-3y-2xy - (2x -3y + xy)+6xy + y - x
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Answer 1

Question:

1. 42a - 52 + 8a - 15b
2. a - (a - b) - b - (2b - a)
3. (5x² + 6x - 3) - (4x - 2x - 8)
4. 2x - 3y -2xy - (2x -3y + xy) + 6xy + y - x

Solution:

1. 42a - 52 + 8a - 15b

= 42a + 8a - 15b - 52

= 50a - 15b - 52

2. a - (a - b) - b - (2b - a)

= a - a + b - b - 2b + a

= a - a + a + b - b - 2b

= a - 2b

3. (5x² + 6x - 3) - (4x - 2x - 8)

= 5x² + 6x - 3 - 4x + 2x + 8

= 5x² + 6x + 2x - 4x - 3 + 8

= 5x² + 4x + 5

4. 2x - 3y - 2xy - (2x - 3y + xy) + 6xy + y - x

= 2x - 3y - 2xy - 2x + 3y - xy + 6xy + y - x

= 2x - 2x - x - 3y + 3y + y - 2xy - xy + 6xy

= - x + y + 3xy