text: how do i write an equation for this line? how would i go about doing the following:  write an equation for the line that passes through the point (7,5) and is perpendicular to the line -7x-9y=14  ?  thanks in advance, i really appreciate it! the equation for a line in slope-intercept form is:  y=mx+b  where m is the slope, and b is the y-intercept.  first you need to rewrite the given equation to get the slope, because the slope of a line perpendicular is the negative reciprocal:  y= (-14/9) - (7/9)x  so the slope of the perpendicular line is the negative reciprocal of -7/9, which is +9/7  so take that slope and the given point, and plug it into the y=mx+b equztion to get your answer:  5=(9/7)(7) + b  b=5-(9/7)(7)  b=-4  equation:  y=(9/7)x - 4