Question
Mathematics Question on Coordinate Geometry
The distance of the origin from the centroid of the triangle whose two sides have the equations
x - 2 y + 1 = 0 and 2 x - y - 1 = 0 and whose orthocenter is (7/3, 7/3) is :
A
√2
B
2
C
2√2
D
4
Answer
√2
Explanation
Solution
The correct answer is (C) : 22
AB = x – 2y + 1 = 0
AC = 2x – y - 1 = 0
So A(1, 1)
Fig. Triangle
Altitude from B is BH =x+2y–7=0⇒B(3,2)
Altitude from C is CH =2x+y–7=0⇒C(2,3)
Centroid of ΔABC = E(2, 2) OE = 22