Start with x^2 +14x = -24,
Find HALF the value of 14: 7
Square this: 49
Add 49, and then subtract 49: x^2 + 14x + 49 - 49 = -24 We have a
perfect square
Rewrite the quadratic as the sq. of a binomial: trinomial on
the left
(x+7)^2 = 25
Take the sqrt of both sides: x+7 = plus or minus 5
Then x = -2 and x = -12