Answer:
Step-by-step explanation:
This is an equilateral triangle, 3 equal sides and 3 equal angles (60°)
so angle C is 60°
you can solve qith an equation
8y - 4 = 60
8y = 60 - 4
8y = 56
y = 56 : 8
y = 7
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check
8y - 4 = 60
(8 * 7) - 4 = 60
56 = 60 - 4
56 = 56
the answer is good
