Question
Question: Orthocentre of the triangle whose vertices are (0, 0) (2, –1) and (1, 3) is....
Orthocentre of the triangle whose vertices are (0, 0) (2, –1) and (1, 3) is.
A
(74,71)
B
(−74,−71)
C
(–4, –1)
D
(4, 1)
Answer
(−74,−71)
Explanation
Solution
Equation of line BC is 4x+y=7 , then equation of line AD is x−4y+k=0 but it passes through (0,0) hence k=0

thus equation of AD=x−4y=0 .....(i)
Similarly the equation of AC=3x−y=0 and BE is
x+3y+1=0 .....(ii)
On solving (i) and (ii), the required orthocentre is (7−4,7−1).