SOLUTION: Find the roots of the quadratic equations by the method of completing the square. Express the roots, if they are not rational, in simplest radical form. x2 + 22x + 112 = 0

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Find the roots of the quadratic equations by the method of completing the square. Express the roots, if they are not rational, in simplest radical form. x2 + 22x + 112 = 0       Log On


   

Question 40974: Find the roots of the quadratic equations by the method of completing the square. Express the roots, if they are not rational, in simplest radical form.


x2 + 22x + 112 = 0
(x - 4 )(x -28 )
check
x^2 +28x -4x +112
x^2+22x+112
thus, (x - 4 )(x -28 )
Found 2 solutions by psbhowmick, lcarpenito:
Answer by psbhowmick(878) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2+%2B+22x+%2B+112+=+0
or %28x%5E2+%2B+2%2Ax%2A11+%2B+11%5E2%29+%2B+112+-+11%5E2+=+0
or %28x+%2B+11%29%5E2+%2B+112+-+121+=+0
or %28x+%2B+11%29%5E2+-+9+=+0
or %28x+%2B+11%29%5E2+=+3%5E2+=+0
or %28x%2B11%29+=+sqrt%283%5E2%29
Either (x+11) = 3 or (x+11) = -3
Accordingly x = -8 or x = -14

Answer by lcarpenito(1) About Me  (Show Source):