Q89 / 150 · MHT CET 2022 (10 Aug Shift 2) · Mathematics
If $A \equiv(5,1, p), B \equiv(1, q, p)$ and $C \equiv(1,-2,3)$ are vertices of the triangle and $G \equiv\left(r,-\frac{4}{3}, \frac{1}{3}\right)$ is its centroid, then the values of $p, q, r$ are respectively
- A$-1,3, \frac{7}{3}$
- B$1,3, \frac{7}{3}$
- C$1,-3, \frac{7}{3}$
- Correct answerD$-1,-3, \frac{7}{3}$
Solution
$\begin{aligned} & \left(r, \frac{-4}{3}, \frac{1}{3}\right) \equiv\left(\frac{5+1+1}{3}, \frac{1+q-2}{3}, \frac{p+p+3}{3}\right) \\ & \Rightarrow r=\frac{7}{3}, \frac{-4}{3}=\frac{q-1}{3}, \frac{1}{3}=\frac{2 p+3}{3} \\ & \Rightarrow p=-1, q=-3, r=\frac{7}{3}\end{aligned}$
Hence, the correct answer is option: 'D'.