How do you evaluate -7a + 11 + 11a = -99 -(-11a) + 4a?

1 Answer
Sep 18, 2017

a=10

Explanation:

-7a+11+11a=-99-(-11a)+4a

First, deal with the bracket on the right side. The product of two negatives is a positive:

-7a+11+11a=-99+11a+4a

Gather like terms on each side:

4a+11=-99+15a

Subtract 15a from both sides and subtract 11 from both sides:

4a-15a+11-11=-99-11+15a-15a

-11a=-110

Divide both sides by -11

(-11a)/-11=-110/-11

a=10

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