Xsquared minus 18x minus 144 equals 0. solve by factoring.

X^2 - 18x - 144 = 0

Factorise:

We choose 2 numbers that add to -18, and multiply to 144, these numbers are +6 and -24, we put it into the brackets:

(x + 6)(x - 24)   <- x = the interted sign of the numbers inside the brackets

E.g. +6 turns into -6 and -24 turns into +24

x must = -6 or = +24