Introductory Algebra for College Students (7th Edition)

Published by Pearson
ISBN 10: 0-13417-805-X
ISBN 13: 978-0-13417-805-9

Chapter 2 - Section 2.5 - An Introduction to Problem Solving - Exercise Set: 15

Answer

$x=14$

Work Step by Step

Let x = the unknown number Then "the sum of 4 and a number" means $4+x$ "twice the sum" means $2(4+x)$ Thus, the equation that represents the situation is: $2(4+x)=36$ Use the distributive property to simplify. $(2\times4)+2x=36$ $8+2x=36$ Use the addition property of equality to subtract 8 from both sides of the equation. $8+2x-8=36-8$ $2x=28$ Use the multiplication property of equality to divide both sides of the equation by 2. $2x\div2=28\div2$ $x=14$
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.