Question

40+3x-x2 spliting the middle term

Answer 1

-x2+3x+40

x2-3x-40

x2-(8-5)x-40

x2-8x+5x-40

x (x-8)+5 (x-8)

(x+5) (x-8)

Answer 2

$\fcolorbox{red}{yellow}{solution } \\ \\ \blue{40 + 3x - {x}^{2}}$

$= - {x}^{2} + 3x + 40 \\ \\ = {x}^{2} - 3x - 40 \\ \\ = {x}^{2} - 8x + 5x - 40 \\ \\ = x(x - 8) + 5(x - 8) \\ \\ = (x + 5)(x - 8)$

$\red{now}$

$\boxed{let}$

$x + 5 = 0 \: \: or \: \: x - 8 = 0 \\ \\ x = - 5 \: \: or \: \: x = 8$

$\underline{i \: hope \: it \: helps \: you}$