Expert: Lynn Houston - 7/29/2009

Question
Write an equation of the line L that satisfies the given conditions. Where possible, express your answer in slope-intercept form. Graph the line.
Question:
Line A passes through the point (7,8) and is perpendicular to the line y=-5 (I have to graph after I solve this problem). How do I set up this equation? Any help would be greatly appreciated.

Answer
y=mx+b

you know x, m and y, so you just need to solve for b to get the value of b for your eq.

Since the line is perpendicular to y = -5 (a horizontal line), that means the line you're looking for is vertical (no slope) and will take the form of x = something.  So this one is actually fairly easy if the point passes through 7,8 and you know its a vertical line, the equation is x = 7.  To graph it, just draw a vertical line (up and down) at x = 7.

Hope this helps.