Solve the equation x^2-4x-21=0

x = 7 and x = - 3

Step-by-step explanation:

x^2-4x-21=0

you can factor to get

(x-7) (x+3) = 0

then set each equal to 0

x - 7 = 0 and x + 3 = 0

then just solve for x!

x = 7 and x = - 3