prove that each of the following two triangles is right angle a)A,B,C:A)(3,5) B)(1,4) C)(2,2)

b)L,M,N:L)(0,-4) M)(6,2) N)(3,5)

a. m(AB) = (4 - 5) / (1 - 3) = -1 / -2 = 1/2 = slope of AB.

m(BC) = (2 - 4) / (2 - 1) = -2 / 1.

AB is perpendicular to BC.
Reason: Their slopes are neg. reciprocals.

Angle B is a rt angle.
Reason; Perpendicular lines form rt angles.

Triangle ABC is a rt triangle.
Reason: If a triangle has one rt angle,it is a rt triangle.

b. Use same procedure as prob. a.