Question

Determine whether the lines through the pairs of points are perpendicular.

A: (2,0) B: (1, -2) and C: (4,2) D: (-8, 4)

I'm ok with the graphs, but I don't know which formula to use. I know that I should use the slope formula to find the slope.

Answer 1

slope=\[slope(m)=(y2-y1)/(x2-x1)\]

Answer 2

if m1*m2=-1 then perpendicular

Answer 3

I thought it was m1= -1/m2

Answer 4

its the same

Answer 5

I got two different answers using both. For the one you told me about I got -1/3 = -1 and for the other formula I got 2 = 6

Answer 6

slope(AB)=2 and slope(CD)=-(1/6)

Answer 7

they are not perpendicular

Answer 8

Thank you. @Gyan_09

Answer 9

you are welcome!