Homework SourseTrue False The triangle defined by the points P1 1 0 Q2 4 1
(True / False) The triangle defined by the points P(1; 1; 0), Q(2; 4; 1), and
R(1; 1; 3) is a right triangle.
R(1; 1; 3) is a right triangle.
Solution
the vector PQ is (2,4,1)-(1,1,0)=(1,3,1) the vector RQ is (1,1,3)-(2,4,1)=(-1,-3,2) the vector PR is (1,1,0)-(1,1,3)=(0,0,-3) PQ*RQ=-1-9+2 is not 0 PQ*PR=-3 RQ*PR=-6 none of these is 0 so none of the pairs of sides is perpendicular So it is not right triangle
