document.write( "Question 984677: Find a if the point (3,a) is on the line that passes through (-2,7) and (5,-3). \n" ); document.write( "
Algebra.Com's Answer #605478 by Cromlix(4381)\"\" \"About 
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Hi there,
\n" ); document.write( "First make up the equation of
\n" ); document.write( "the line between (-2,7) and(5,-3)
\n" ); document.write( "Gradient = y2 - y1/x2 - x1
\n" ); document.write( "Gradient = -3-7/5-(-2)
\n" ); document.write( "Gradient = -10/7
\n" ); document.write( "Using equation of line formula:
\n" ); document.write( "y - b = m(x - a)
\n" ); document.write( "using m = -10/7 and (a,b)= (-2,7)
\n" ); document.write( "y - 7 = -10/7(x - (-2))
\n" ); document.write( "y - 7 = -10/7(x + 2)
\n" ); document.write( "y - 7 = -10/7x - 20/7
\n" ); document.write( "y = -10/7x - 20/7 + 49/7 (7)
\n" ); document.write( "y = -10/7x + 29/7
\n" ); document.write( "This is your equation.......
\n" ); document.write( "............................
\n" ); document.write( "Now substitute the points coordinates
\n" ); document.write( "into the equation:
\n" ); document.write( "y = -10/7x + 29/7
\n" ); document.write( "y = -10/7(3) + 29/7
\n" ); document.write( "y = -30/7 + 29/7
\n" ); document.write( "So, y = -1/7
\n" ); document.write( "Point coords (3, -1/7)
\n" ); document.write( "Hope this helps:-) \n" ); document.write( "
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