SOLUTION: Solve using the quadratic form. One-half the square of a number is equal to 16 more than twice the number. What is the number?

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Question 1143994: Solve using the quadratic form.
One-half the square of a number is equal to 16 more than twice the number. What is the number?
Answer by greenestamps(13198) About Me  (Show Source):
You can put this solution on YOUR website!


Let the number be x.

One-half the number squared is (1/2)x^2.

16 more than twice the number is 2x+16.

Write and solve the equation that says those two expressions are equal:

%281%2F2%29x%5E2+=+2x%2B16

It's a quadratic equation. Get everything on one side of the equation (with 0 on the other side) and try to solve using factoring; if it doesn't factor (or you can't see how it factors), use the quadratic formula.

(If you know the basics about solving quadratic equations, you will start by multiplying the whole equation by 2 to get rid of the fractions....)