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You can put this solution on YOUR website!
first you want to find the slope.
\n" ); document.write( "slope = (y2-y1)/x2-x1)
\n" ); document.write( "let(x1,y1) = (3,2)
\n" ); document.write( "let(x2,y2) = (12,1)
\n" ); document.write( "this makes:
\n" ); document.write( "y2 = 1 and y1 = 2
\n" ); document.write( "x2 = 12 and x1 = 3
\n" ); document.write( "formula becomes (y2-y1)/(x2-x1) = (1-2)/(12-3) = -1/9
\n" ); document.write( "the slope intercept form of the equation for a straight line is y = mx + b
\n" ); document.write( "m is the slope and b is the y-intercept.
\n" ); document.write( "since the slope is -1/9, the formula becomes y = -1/9 * x + b
\n" ); document.write( "replace x and y with either one of the points on the line to find the value of b.
\n" ); document.write( "i used the point (3,2) to get 2 = -1/9 * 3 + b
\n" ); document.write( "simplify to get 2 = -3/9 + b
\n" ); document.write( "solve for b to get b = 2 + 3/9 = 18/9 + 3/9 = 21/9.
\n" ); document.write( "the equation of y = mx + b becomes y = -1/9 * x + 21/9
\n" ); document.write( "when x = 3, this equation becomes y = -1/9 * 3 + 21/9 which becomes y = -3/9 + 21/9 which becomes y = 18/9 which becomes y = 2 which is true.
\n" ); document.write( "when x = 12, this becomes y = -1/9 * 12 + 21/9 which becomes y = -12/9 + 21/9 which becomes y = 9/9 which becomes y = 1, which is true.
\n" ); document.write( "the equation is y = -1/9 * x + 21/9
\n" ); document.write( "that's your solution. \n" ); document.write( "