Expert: Lynn Houston - 2/9/2010

Question
What is the slop of the line perpendicular to the line whose equation is 5x+3y=8?

Ive been working on this problem for a while and i just can't seem to get it right

Answer
5x+3y=8  Put into slope intercept form

3y = -5x + 8
y = -5/3x + 8/3  The slope of this line is -5/3, so a line perpendicular to it has a slope of 3/5.

Now, find a point on the line, if x =3, y = 3.  Use this point and the slope to find the y intercept of the perpendicular line

3 = 3/5(3) + b  solve for b
3 = 9/5 + b
6/5 = b so, the equation of a line perpendicular to 5x+3y=8 is y = 3/5x + 6/5