Answer:
y + 5 = m(x - 2)
Step-by-step explanation:
To write an equation of a new line perpendicular to x-4y= 20, we need the slope of the original line first. Solving this equation for y, we get x - 20 = 4y, or y = (1/4)x - 5. The slope of the original line is 1/4. The slope of a line perpendicular to the given line is the negative reciprocal of this 1/4, which turns out to be -4.
Now we have the slope (-4) of the desired new line, plus one point on this line, (2, -5). Start with the point-slope form y - k = m(x - h). Substitute 2 for h, -5 for k and -4 for m, obtaining:
y + 5 = m(x - 2) This line is perpendicular to x-4y= 20.
