document.write( "Question 762959: Given: AX || CY
\n" ); document.write( "BA bisects ∠CAX,
\n" ); document.write( "BC bisects ∠ACY.
\n" ); document.write( "Prove: ∠B is a right angle.\r
\n" ); document.write( "\n" ); document.write( "Diagram looks like a triangle (where it's pointed end is pointing in the right) in the middle of the parallel lines. \r
\n" ); document.write( "\n" ); document.write( "Looks something like this:\r
\n" ); document.write( "\n" ); document.write( "A
\n" ); document.write( "__________X
\n" ); document.write( "|
\n" ); document.write( "| .C
\n" ); document.write( "|_________Y
\n" ); document.write( "B\r
\n" ); document.write( "\n" ); document.write( "Has to be written as Statements & Reasons. I really want to know how to do this!
\n" ); document.write( "

Algebra.Com's Answer #464610 by ramkikk66(644)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "See the picture below which describes your problem. I have extended line CA further upwards to a point P, which is required for the proof.\r
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "\n" ); document.write( "Problem:
\n" ); document.write( "AX || CY
\n" ); document.write( "BA bisects ?CAX,
\n" ); document.write( "BC bisects ?ACY.
\n" ); document.write( "Prove: ?B is a right angle. \r
\n" ); document.write( "\n" ); document.write( "Step 1:
\n" ); document.write( "BA bisects angle CAX. So angle CAB = angle BAX\r
\n" ); document.write( "\n" ); document.write( "Step 2:
\n" ); document.write( "BC bisects angle ACY. So angle ACB = angle BCY\r
\n" ); document.write( "\n" ); document.write( "Step 3:
\n" ); document.write( "Angle PAX = angle ACY since AX || CY (external angles of parallel lines)\r
\n" ); document.write( "\n" ); document.write( "Step 4:
\n" ); document.write( "Angles PAX + CAX = 180 (supplementary angles on a straight line)\r
\n" ); document.write( "\n" ); document.write( "Step 5:
\n" ); document.write( "i.e. PAX / 2 + CAX / 2 = 90\r
\n" ); document.write( "\n" ); document.write( "Step 6:
\n" ); document.write( "ACY / 2 + CAX / 2 = 90 Since PAX = ACY\r
\n" ); document.write( "\n" ); document.write( "Step 7:
\n" ); document.write( "ACB + CAB = 90 Since ACB is half of ACY, CAB is half of CAX\r
\n" ); document.write( "\n" ); document.write( "Step 8:
\n" ); document.write( "But in Triangle ABC, ACB + CAB + ABC = 180\r
\n" ); document.write( "\n" ); document.write( "Step 9:
\n" ); document.write( "So ABC = Angle B = 90\r
\n" ); document.write( "\n" ); document.write( ":)\r
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