Question

13. In triangle ABC, AB= √3a, AC = a and BC = 2a. Prove that ∟A = 90˚

Answer 1

AB= √3a, AC = a and BC = 2a AB^2+AC^2=BC^2 (√3a)^2+a^2=(2a)^2 3a^2+a^2=4a^2 4a^2=4a^2 LHS=RHS IT FOLLOWS PATHOGIRUS THEROM SO ANGLE A =90