Solve 9(a+b)^2-25

$$9 ( a + b ) ^ { 2 } - 25$$

Evaluate

$$\left(3a+3b\right)^{2}-25$$

Solution Steps

Use binomial theorem \left(p+q\right)^{2}=p^{2}+2pq+q^{2} to expand \left(a+b\right)^{2}.

$$9\left(a^{2}+2ab+b^{2}\right)-25$$

Use the distributive property to multiply 9 by a^{2}+2ab+b^{2}.

$$9a^{2}+18ab+9b^{2}-25$$

Expand

$$9a^{2}+18ab+9b^{2}-25$$

Solution Steps

Use binomial theorem \left(p+q\right)^{2}=p^{2}+2pq+q^{2} to expand \left(a+b\right)^{2}.

$$9\left(a^{2}+2ab+b^{2}\right)-25$$

Use the distributive property to multiply 9 by a^{2}+2ab+b^{2}.

$$9a^{2}+18ab+9b^{2}-25$$