Question

A triangle ABC is drawn on a coordinate plane . Find the length of the side BC.

Answer 1

B(3 , 5) and C(2 , -3)

Distance BC = √[(2 - 3)^2 + (-3-5)^2]

= √(1 + 64)

= √65

Answer

A. √65 units

Answer 2

BC is the longest side of the triangle BCC', where C' is located one cube to the right of C, so the CC' = 1 and BC' = 8. Using the Pythagoras theorem, we will find the BC easily : BC^2 = BC'^2 + CC'^2 = 1^2 + 8^2 = 1 + 64 = 65, so the BC = square root of 65.