document.write( "Question 773696: if AB is parallel to CD find the value of a if A(-2,4) B(3,5) C(-1,-3) D(4,a) \n" ); document.write( "
Algebra.Com's Answer #471761 by Cromlix(4381)\"\" \"About 
You can put this solution on YOUR website!
Using equation for slope.
\n" ); document.write( "y2 - y1/x2 - x1
\n" ); document.write( "AB
\n" ); document.write( "5 - 4/3 -(-2)
\n" ); document.write( "1/5
\n" ); document.write( "CD
\n" ); document.write( "a -(-3)/4 -(-1)
\n" ); document.write( "a + 3/5
\n" ); document.write( "Lines that are parallel have
\n" ); document.write( "slopes that equal one another.
\n" ); document.write( "m1 = m2
\n" ); document.write( "1/5 = a + 3/5
\n" ); document.write( "a + 3 = 1
\n" ); document.write( "a = 1 - 3
\n" ); document.write( "a = -2
\n" ); document.write( "Hope this helps.
\n" ); document.write( ":-) \n" ); document.write( "
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