Show that the points A, B and C below are the vertices of a right triangle, if A(−4,3), B(3,2), and C(−1,−1)

Question

Show that the points A, B and C below are the vertices of a right triangle, if A(−4,3), B(3,2), and C(−1,−1)

Answer 1

slope of CB = (2+1)/(3+1) = 3/4

slope of AC = (3+1)/(-4+1) = 4/-3

their slopes are negative inverses, which means AC and CB are perpendicular

If two sides of a triangle are perpendicular, it's a right triangle.

it helps to plot the 3 points, connect them with line segments, and you'll get a good clue

which two sides you need to check for slopes. Even a very rough sketch willl tell

you it's sides AC and CB