**Q) **Show that the points (-2, 3), (8, 3) and (6, 7) are the vertices of a right-angled triangle.

**Ans: **Let’s plot these points on graph, we get:

Then, AB = 10,

BC = **√(**4 + 16) = **√**20

AC = **√** (64 +16) = **√**80

Since, (10)** ^{ 2 }** = (

**√**20)

**+ (**

^{ 2 }**√**80)

^{ 2}Or AC** ^{2 }**= AB

**+ BC**

^{2 }

^{2 }**Therefore, triangle ABC is a right-angled triangle.**