Question

If the vertices of a triangle be (a, 1), (b, 3) and (4, c), then the centroid of the triangle will lie on x-axis, if-

• A. a + c = –4
• B. a + b = –4
• C. c = – 4
• D. b + c = – 4

Answer 1

Answer: (C)

c = – 4

Answer 2

centroid $\left( \frac{a + b + 4}{3},\frac{1 + 3 + C}{3} \right)$

it lies on x – axis

\ y-co-ordinate = 0; $\frac{4 + C}{3}$ = 0

C = - 4 \end{matrix}$$