Intermediate Algebra (6th Edition)

Published by Pearson
ISBN 10: 0321785045
ISBN 13: 978-0-32178-504-6

Chapter 5 - Section 5.6 - Factoring Trinomials - Exercise Set - Page 303: 8

Answer

$(x+3)(x-12)$

Work Step by Step

In order to factor $x^{2}-9x-36$, we must find a pair of numbers whose product is equal to -36 (or the constant term) and whose sum is equal to -9 (or the coefficient on the middle term). We know that only a pair of one positive and one negative number will produce a negative product and a negative sum. We know that the pairs of numbers whose product is -36 are -1,36, 1,-36, -2,18, 2,-18, -3,12, 3,-12, -4,9, 4,-9, and 6,-6. Out of these pairs, the sum of 3 and -12 is equal to -9. Therefore, $x^{2}-9x-36=(x+3)(x-12)$.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.