document.write( "Question 1058333: In the city of Marble Springs, Main Street intersects some of the other avenues in town. On a coordinate grid, Main Street passes through the points (-2,17) and (-22,33). Grimes boulevard, a street that is perpendicular to Main Street, passes through the point (80,9). Write the equation of the line that represents Grimes Boulevard in slope-intercept form. \n" ); document.write( "
Algebra.Com's Answer #673373 by Cromlix(4381)\"\" \"About 
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Hi there,
\n" ); document.write( "Find the gradient (Slope) of Main Street using the
\n" ); document.write( "coordinates that it intersects.
\n" ); document.write( "(-2, 17) and (-22, 33)
\n" ); document.write( "Gradient (Slope) = y2 - y1/x2 - x1
\n" ); document.write( "Gradient(Slope) = 33 - 17/-22 -(-2)
\n" ); document.write( "Gradient (Slope) = 33 - 17/-22 + 2
\n" ); document.write( "Gradient (Slope) = 16/-20 = -4/5
\n" ); document.write( "Lines that are perpendicular to one
\n" ); document.write( "another have gradients (slopes) that
\n" ); document.write( "multiply together to give -1
\n" ); document.write( "m1 x m2 = -1
\n" ); document.write( "-4/5 x m2 = -1
\n" ); document.write( "m2 = 5/4
\n" ); document.write( "Using the straight line equation:
\n" ); document.write( "y - b = m(x - a)
\n" ); document.write( "where m = 5/4 and (a,b) = (80, 9)
\n" ); document.write( "y - b = m(x - a)
\n" ); document.write( "y - 9 = 5/4(x - 80)
\n" ); document.write( "y - 9 = 5/4x - 100
\n" ); document.write( "y = 5/4x - 100 + 9
\n" ); document.write( "y = 5/4x - 91
\n" ); document.write( "This is the equation of Grimes
\n" ); document.write( "Boulevard in slope - intercept form.
\n" ); document.write( "Hope this helps :-) \n" ); document.write( "
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