What is the value of g in the center and how do you solve it?

First solve:
7 + 3c = -11 --> c = -6
-9 - a/4 = 5 --> a = -56
b/5 +9 = 6 --> b = 75

second, solve:
a/f = -7 --> substitute -56 in for a --> -56/f = -7 --> f = 8
b/e = 3 --> substitute 75 in for b --> 75/e = 3 --> e = 25
3 = c/d --> substitutie -6 in for c --> 3 = -6/d --> d = -2

third solve:
g = d+e+f --> substitute -2 in for d, 25 in for e, and 8 in for f.
g = -2 + 25+8 
g = 31

Lets find out d first:

3 = c/d => d = c/3

7+3c = -11 => 3c = -11 - 7 => 3c = -18 => c = -18/3 => c = -6.

Now d = c/3 => d = -6/3 => d = -2.

Lets now find out e:

b/e = 3 => e = b/3

b/5 + 9 = 6 => b = (6-9)*5 => b = -15

Now e = b/3 => e = -15/3 = -5

Now we need to find f:

a/f = -7 => f = a/-7

-9 - a/4 =5 => a= (-9-5)*4 = -56

Now f = a/-7 => f = -56 / -7 = 8

So g = d + e + f
= (-2) + (-5) + 8
= 1
Therefore g = 1

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