Answer:
Step-by-step explanation:
x^2 - 6x - 40 = 0.....get the -40 to the other side
x^2 - 6x = 40....now take half of ur x term (6)....so its 3...then square it (3^2 = 9)...now add 9 to both sides
x^2 - 6x + 9 = 40 + 9
(x - 3)(x - 3) = 49
(x - 3)^2 = 49...take sqrt of both sides, eliminating the ^2
x - 3 = sqrt 49
x = 3 (+ - ) 7
x = 3 + 7 = 10 or x = 3 - 7 = -4
so x = 10 or x = -4
