Evan F. answered 11/08/19
B.S. in Mathematics and M.S.Ed. with 10+ Years of Teaching Experience
Perpendicular to 4y+20x = -20 and passes through (5,-1)
1st step: Solve for y in terms of x
4y+20x = -20
-20x -20x
4y= -20-20x
÷4 ÷4
y=-5x-5
2nd Step: Find slope
m=-5
3rd Step: Find perpendicular slope which is the negative reciprocal of the slope of the original line
Perpendicular slope = 1/5
4th Step: Use pass through coordinate (5,-1) and perpendicular slope to find the equation of the line by using the point slope formula y -y1 = m(x-x1) and solve for y in terms of x.
y-(-1)=1/5(x-5)
y+1=(1/5)x-1
-1 -1
y=(1/5)x - 2
Done