Question

1. (2x + 3)(x - 5) - 4x(3x + 7)

Explanation:

Step1: Expand first product

$(2x+3)(x-5) = 2x\cdot x + 2x\cdot(-5) + 3\cdot x + 3\cdot(-5) = 2x^2 -10x +3x -15 = 2x^2 -7x -15$

Step2: Expand second product

$4x(3x+7) = 4x\cdot3x + 4x\cdot7 = 12x^2 +28x$

Step3: Subtract the two expansions

$(2x^2 -7x -15) - (12x^2 +28x) = 2x^2 -7x -15 -12x^2 -28x$

Step4: Combine like terms

$(2x^2-12x^2) + (-7x-28x) -15 = -10x^2 -35x -15$

Answer:

$-10x^2 -35x -15$