Question

(ii) (3x + 4) (3x - 5) use suitable identity

​

Answer 1

Answer: $9x^2-3x-20$

Explanation:

$\begin{aligned}(3x+4)(3x-5)&=(3x)(3x)+(3x)(-5)+(4)(3x)+(4)(-5)\\&=9x^2-15x+12x-20\\&=9x^2-3x-20\end{aligned}$

Answer 2

Answer:

no

only then (3x+4)(3x-4)