Answer: 120
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Explanation:
Use the first equation and b = 30 to find c
b+c = 90
30+c = 90
c = 90-30
c = 60
This leads to e = 60 due to the third equation given to you.
Then finally we can use the second equation e+w = 180 to get:
e+w = 180
60+w = 180
w = 180-60
w = 120
