<PRE><B>Question 162224</B>
Given two angles that form a linear pair. Prove that their bisectors are perpendicular. 
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Let the angles be A and B.
A + B = 180 degrees ; def. of linear pair
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Let L1 be a bisector of A forming a1 and a2
Let L2 be a bisector of B forming b1 and b2
Let a1 be ajacent to b1
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a1=a2 and b1=b2; def. of bisector
a1+a2 = A and b1+b2 = B; def. of bisector
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2a1 = A and 2b1 = B; substitution
2a1 + 2b1 = 180 ; substitution
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a1 + b1 = 90 ; equals divided by equals are equal
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L1 and L2 are perpendicular ; def of perpendicular
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Cheers,
Stan H.

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