Question
Question: The equation of the plane through the three points (1, 1, 1), (1, –1, 1) and (–7,–3,–5), is...
The equation of the plane through the three points (1, 1, 1), (1, –1, 1) and (–7,–3,–5), is
A
3x−4z+1=0
B
3x−4y+1=0
C
3x+4y+1=0
D
None of these
Answer
3x−4z+1=0
Explanation
Solution
Plane passing through (1, 1, 1) is
a(x−1)+b(y−1)+c(z−1)=0
It also passes through (1, – 1, 1) and (–7, – 3, – 5), then b=0,a=−43c
Hence the required equation is 3x−4z+1=0.
Trick : Since the plane 3x−4z+1=0 passes through given three points.