If two vertices of a triangle are (5, 4) and (-2, 4) and centroid is (5, 6), then third vertex is: |
(10, 12) (12, 10) (-10, -12) (12, -10) |
(12, 10) |
The correct answer is Option (2) → (12, 10) Let the vertices of the triangle be $A(5,4), B(-2,4), C(x, y)$. The centroid formula: $G = \left( \frac{x_1 + x_2 + x_3}{3}, \frac{y_1 + y_2 + y_3}{3} \right)$ Given $G = (5, 6)$: $\frac{5 + (-2) + x}{3} = 5 ⇒ \frac{3 + x}{3} = 5 ⇒x + 3 = 15 ⇒x = 12$ $\frac{4 + 4 + y}{3} = 6 ⇒\frac{8 + y}{3} = 6 ⇒8 + y = 18 ⇒y = 10$ Third vertex: $C = (12, 10)$ |