document.write( "Question 1009166: Find the value of a if the interval joining (-5, -2) and (-3, a) has a gradient of -3/4.\r
\n" ); document.write( "\n" ); document.write( "Thanks. \n" ); document.write( "
Algebra.Com's Answer #624806 by LinnW(1048)\"\" \"About 
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Using the template y = Mx + b
\n" ); document.write( "Use the point (-5,-2). Substitute -5 for x, -2 for y and
\n" ); document.write( " -3/4 for M
\n" ); document.write( "-2 = (-3/4)(-5) + b
\n" ); document.write( "-2 = 15/4 + b
\n" ); document.write( "add -15/4 to each side
\n" ); document.write( "-2 -15/4 = b
\n" ); document.write( "-8/4 -15/4 = b
\n" ); document.write( "-23/4 = b
\n" ); document.write( "So our equation is y = (-3/4) x -23/4
\n" ); document.write( "To solve for a in the pair (-3,a) , substitute a for y, and -3 for x
\n" ); document.write( "a = (-3/4)(-3) -23/4
\n" ); document.write( "a = 9/4 -23/4
\n" ); document.write( "a = -14/4
\n" ); document.write( "a = -7/2
\n" ); document.write( "our two points are (-5,-2) and (-3,-7/2)
\n" ); document.write( "We can verify our result.
\n" ); document.write( "The gradient = (y2-y1)/(x2-x1)
\n" ); document.write( "(-7/2-(-2))/(-3-(-5)) =
\n" ); document.write( "(-7/2 + 4/2)/(-3+5)
\n" ); document.write( "(-3/2)/2
\n" ); document.write( "-3/4
\n" ); document.write( " \n" ); document.write( "
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