MiMi M. answered • 03/03/16

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Certified Math Teacher - MiMi

The given line has a slope of -1/3 so a line perpendicular would have a slope of 3.

Using y = mx + b, you then have 4 = 3(-5) + b. Solving for b you get 4 = -15 + b, so b = 19. Your equation will then be y = 3x + 19.

m is the slope, so the original equation had a slope of -1/3.

Perpendicular lines have slopes which are opposite reciprocals. When you multiply the two slopes you get an answer of -1. -1/3 * 3 = -1

If you have the point (-5, 4), x = -5 and y = 4. Using y = mx + b, this gives you 4 = 3*-5 + b.

4 = -15 + b

add 15 to both sides to solve for b: 19 = b

Chris C.

03/03/16