5.3
(x-2)(x+7)
x(x) + 7x - 2x - 2(7)
x2 + 7x - 2x - 14
= x2 + 5x - 14
(8x3 - 12x) / (4x2)
4x(2x2 - 3) / 4x2
= 2x2 - 3 / x
(6x-7)(2x+5)
(6x(2x)) + (6x(5)) - (7(2x)) - 7(5)
12x2 + 30x - 14x - 35
= 12x2 + 16x - 35
5x2 + 2x + 3 / x+2
= 5x - 8 + 19/x+2
(x2 + 6x - 5)(4x + 2)
x2(4x+2) + 6x(4x+2) - 5(4x+2)
4x3 + 2x2 + 24x2 + 12x - 20x - 10
= 4x3 + 26x2 - 8x - 10
(4x2 - 2x) / (-x)
4x2/-x - 2x/-x
= -4x + 2