Hey!
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Solution:
~Substitute
45 + 57 = 37 + y
~Subtract y to both sides
45 + 57 - y = 37 + y - y
~Simplify
102 - y = 37
~Subtract 102 to both sides
102 - y - 102 = 102 - 37
~Simplify
y = 65
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Answer:
y = 65
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Hope This Helped! Good Luck!