Question

The three points (–2,2), (8,–2) and (–4, –3) are the vertices of.

• A. An isosceles triangle
• B. An equilateral triangle
• C. A right angled triangle
• D. None of these

Answer 1

Answer: (C)

A right angled triangle

Answer 2

$a = \sqrt { ( 8 + 2 ) ^ { 2 } + ( - 2 - 2 ) ^ { 2 } } = \sqrt { 116 }$

$b = \sqrt { ( - 4 - 8 ) ^ { 2 } + ( - 3 + 2 ) ^ { 2 } } = \sqrt { 145 }$

$c = \sqrt { ( - 4 + 2 ) ^ { 2 } + ( - 3 - 2 ) ^ { 2 } } = \sqrt { 29 }$ $\Rightarrow a ^ { 2 } + c ^ { 2 } = b ^ { 2 }$

Hence it is right angled triangle.