If GH = 45 and GI = 61, then what does HI equal?

1. If GH=31 and HI=11 then GI = GH+HI = 31+11 = 42

2. If GH=45 AND GI = 61 then HI = GI-HG = 61-45 = 16

a. what is the value of Y?

Since GI = GH+HI

9Y+7 = 7Y+3+3Y-5

9Y+7 = 10Y-2

Y = 9

b. Find

GH = 7Y+3 = 7*9+3 = 66

HI = 3Y-5 = 3*9-5 = 22

GI = 9Y+7 = 9*9+7 = 88