for a triangle all angles add up to 180 degrees.
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m<1 = 2x + 1. m<1 + m<2 = 5x. (2x + 1) + m<2 = 5x. 2x + 1 + m<2 = 5x. 1 + m<2 = 5x  2x. 1 + m<2 = 3x. m<2 = 3x  1. To get an actual value for x, we would
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An angle addition postulate states that if a point S lies in the interior of PQR, then PQS +
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If S is in the interior of angle PQR then measure angle PQS + measure angle SQR= measure angle PQR.
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