Question

without using Pythagoras theorem, prove that the points A (1,3), B (3,-1) and C (-5,-5) are the vertices of a right angled triangle ​

Answer 1

Answer:

AB=√(1-3)^2+(3+1)^2

=√4+16

=√20

BC=√(3+5)^2+(5-1)^2

=√64+16

=√80

AC=√(1+5)^2+(3+5)^2

=√36+64

=10

BY USING Pythagoras theorem,

AB^2+BC^2=AC^2

=20+80=100

SINCE

LHS=RHS

HENCE PROVED.