Question

The expression (3x - 4) (3x + 1) is equal to

Answer 1

Answer:

(3x-4)(3x+1)

(x+a)(x+b) = x^2 + (a+b)x + ab

(3x-4)(3x+1) = (3x)^2 + (-4+1)×3x +(-4)×1

= 9x^2 + (-3)×3x -4

= 9x^2 -9x -4

Answer 2

Answer:

this expression is equal to

$9 {x}^{2} \: + \: 3 {x}(1 - 4) \: + \: ( - 4)(1) \\ = 9 {x}^{2} - 9 {x} - 4$