Question 204090
Let  x, y =  angles  of  parallelogram.
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sum  of  angles  = 2x +2y = 360
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but x=(2y-15),,,given
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subst
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2(2y-15) +2y =360
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4y -30 +2y =360
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6y =390
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y= 65,,,,,,,x=2y-25 =2(65)-15 = 115
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check 65 +115 = 180,,,ok  both  supplemental  and  1/2  of 360
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