document.write( "Question 1024083: The points that passes through the line (2,3) and is perpendicular to the line that passes through the points (4,5) and (9,12) ..? \n" ); document.write( "
Algebra.Com's Answer #639542 by Cromlix(4381)\"\" \"About 
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Hi there,
\n" ); document.write( "Gradient (slope) of line that passes through
\n" ); document.write( "(4,5) and (9,12)
\n" ); document.write( "Gradient (slope) = y2 - y1/x2 - x1
\n" ); document.write( "Gradient (slope) = 12 -5/9 - 4
\n" ); document.write( "Gradient (slope) = 7/5
\n" ); document.write( "Lines that are perpendicular to one another
\n" ); document.write( "have gradients (slopes) that multiply together
\n" ); document.write( "to give -1
\n" ); document.write( "m1 x m2 = -1
\n" ); document.write( "Using 7/5
\n" ); document.write( "7/5 x m2 = -1
\n" ); document.write( "m2 = -5/7
\n" ); document.write( "Setting up the line using the line equation
\n" ); document.write( "y - b = m(x - a)
\n" ); document.write( "m = -5/7 (a,b) = (2,3)
\n" ); document.write( "y - 3 = -5/7(x - 3)
\n" ); document.write( "y - 3 = -5/7x + 15/7
\n" ); document.write( "y = -5/7x + 15/7 + 21/7 (3)
\n" ); document.write( "y = -5/7x + 36/7
\n" ); document.write( "or multiply through by 7
\n" ); document.write( "7y = -5x + 36.
\n" ); document.write( "Points on this line can be:-
\n" ); document.write( "(3,3)
\n" ); document.write( "7y = -5(3) + 36
\n" ); document.write( "7y = -15 + 36
\n" ); document.write( "7y = 21
\n" ); document.write( "y = 3
\n" ); document.write( "(10,-2)
\n" ); document.write( "7y = -5x + 36
\n" ); document.write( "7y = -5(10) + 36
\n" ); document.write( "7y = -14
\n" ); document.write( "y = -2.
\n" ); document.write( "Hope this helps :-) \n" ); document.write( "
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