Question

Find the value of a.

A.
3
B.
5
C.
8
D.
11

Answer 1

The triangles are similar, so we can set up this proportion

\[\Large \frac{a+5}{12} = \frac{12}{18}\]

Answer 2

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

Answer 3

what is my next step

Answer 4

@jim_thompson5910 a = 3 correct??

Answer 5

a = 3 is correct

Answer 6

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

Answer 7

ty