Solve b^2-16/9b+36div4-b/9

$$\frac { b ^ { 2 } - 16 } { 9 b + 36 } \div \frac { 4 - b } { 9 }$$

Evaluate

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Short Solution Steps

Divide \frac{b^{2}-16}{9b+36} by \frac{4-b}{9} by multiplying \frac{b^{2}-16}{9b+36} by the reciprocal of \frac{4-b}{9}.

$$\frac{\left(b^{2}-16\right)\times 9}{\left(9b+36\right)\left(4-b\right)}$$

Factor the expressions that are not already factored.

$$\frac{9\left(b-4\right)\left(b+4\right)}{9\left(b+4\right)\left(-b+4\right)}$$

Extract the negative sign in -4+b.

$$\frac{-9\left(b+4\right)\left(-b+4\right)}{9\left(b+4\right)\left(-b+4\right)}$$

Cancel out 9\left(b+4\right)\left(-b+4\right) in both numerator and denominator.

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Factor

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