SOLUTION: Find the roots of x^2+11x=-30

Algebra ->  Probability-and-statistics -> SOLUTION: Find the roots of x^2+11x=-30      Log On


   

Question 985928: Find the roots of x^2+11x=-30
Found 2 solutions by ikleyn, MathTherapy:
Answer by ikleyn(52832) About Me  (Show Source):
You can put this solution on YOUR website!
.
x%5E2 + 11x = -30

x%5E2 + 11x + 30 = 0.

Use the Vieta's theorem  Solving quadratic equations without quadratic formula  to find the roots without using the quadratic formula:

x%5B1%5D = -5, x%5B2%5D = -6.


Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

Find the roots of x^2+11x=-30
x%5E2+%2B+11x+=+-+30

x%5E2+%2B+11x+%2B+30+=+0

(x + 6)(x + 5) = 0 ------- Factoring the trinomial

Solving for x gives: highlight_green%28system%28x+=+-+6_or%2Cx+=+-+5%29%29