document.write( "Question 39747: can you help me?
\n" ); document.write( "What is the equation of the line that passes through the points (-2,2) and (0,5) ? \n" ); document.write( "
Algebra.Com's Answer #25170 by Fermat(136)\"\" \"About 
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If you have two points, (x1,y1) and (x2,y2) then the slope of the line joining them is given by,
\n" ); document.write( "m = (y1-y2) / (x1-x2)
\n" ); document.write( "We have (x1,y1) = (-2,2) and (x2,y2) = (0,5) so,
\n" ); document.write( "m = (2 - 5) / (-2 - 0) = -3/-2
\n" ); document.write( "m = 1.5
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\n" ); document.write( "The equation of any straight line can be written as,
\n" ); document.write( "y = mx + c
\n" ); document.write( "where m is the slope and c is the y-intercept.
\n" ); document.write( "The slope of the line joining (-2,2) and (0,5) is m = 1.5. So the eqn is,
\n" ); document.write( "y = 1.5x + c
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\n" ); document.write( "Any point on this line will satisfy the equation of the line. That means that we can put the x- and y-coordinates into the equation and we will get the lhs = the rhs.
\n" ); document.write( "The point (0,5) is one of the points we know lies on the line, so its x- and y-coordinates will satisfy the equation of the line if we we put x = 0 and y = 5 into the equation. This gives us,
\n" ); document.write( "5 = 0 + c
\n" ); document.write( "Since lhs = rhs, then
\n" ); document.write( "c = 5
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\n" ); document.write( "Finally,
\n" ); document.write( "y = 1.5x + 5
\n" ); document.write( "============ \n" ); document.write( "
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