Math problem plz solve

Question

x²-3x=40

Plz help me solve

Answer 1

Hello Caleb.

Get a polynomial first, so cancel 40 at right

x^2 -3x -40 =0. You need to check factors of -40 which sum of these give you -3;

-40 = -40*1 (not this one)

-20 *2. (not this one)

-10*4 (not this one)

-8*5. (Yes!)

x^2 -3x -40 = (x-8)(x+5) =0

x-8 = 0 and x=8, x+5 =0 and x= -5

hope that helps