Answer: s = 29
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Work Shown
Rule: The three interior angles of any triangle always add to 180
(angle1)+(angle2)+(angle3) = 180
(64)+(2s)+(2s) = 180
4s+64 = 180
4s+64-64 = 180-64 ..... subtracting 64 from both sides
4s = 116
4s/4 = 116/4 ............ dividing both sides by 4
s = 29
