Question

What’s the correct answer for this?

Answer 1

AB(y = ax + b) contains A(2, 1) and B(3, 4)

=> 2a + b = 1

3a + b =4

=> a = 3, b= -5 => Slope AB = a = 3

CD (y = cx + d) contains C(-2, -1) and D(1, -2)

=> -2c + d = -1

c + d = -2

=> c = -1/3, d = -5/3 => Slope CD = c =-1/3

If AB is perpendicular to CD, then Slope's AB x Slope's CD = -1

Check:

a x c = 3 x (-1/3) = -1

=> AB is perpendicular to CD

=> Option B is correct.

Hope this helps!

:)

Answer 2

B.

Explanation:

Yes, because the product of their slopes are -1. Rest explanation in the attached file. Hope it helps :)