Question

(3x+4)(3x-5) by using the identity what will be the answer ?? .
pls do it fast

Answer 1

(3x+4)[3x+(-5)
by using identity(4)
9x^2-3x-20

Answer 2

Here is your answer⬇️

By using the identity ⬇️

(x+a) (x+b) = x² + (a+b)x + ab

Here x = 3x , a = 4 , b = (-5)

$\therefore{(3x+4) (3x-5)}$

= (3x)² + (4-5)3x + (4 × -5)

= 9x² + (-3x) + (-20)