## A community for students. Sign up today

Here's the question you clicked on:

## anonymous one year ago Find the value of a. A. 3 B. 5 C. 8 D. 11

• This Question is Closed
1. anonymous

2. jim_thompson5910

The triangles are similar, so we can set up this proportion $\Large \frac{a+5}{12} = \frac{12}{18}$

3. jim_thompson5910

cross multiply to get $\Large \frac{a+5}{12} = \frac{12}{18}$ $\Large (a+5)*18 = 12*12$ $\Large 18*(a+5) = 144$ $\Large 18a+90 = 144$ I'll let you finish up

4. anonymous

what is my next step

5. anonymous

@jim_thompson5910 a = 3 correct??

6. jim_thompson5910

a = 3 is correct

7. jim_thompson5910

18a + 90 = 144 18a + 90 - 90 = 144 - 90 ... Subtract 90 from both sides. 18a = 54 18a/18 = 54/18 ... Divide both sides by 18. a = 3

8. anonymous

ty

#### Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy