Concept:Two lines intersect when their parametric coordinates become equal for some values of the parameters.
Explanation:Write the first line using parameter
λ:
x=3+λ,y=5+2λ,z=1−λWrite the second line using parameter
μ:
x=4+2μ,y=2−μ,z=4+2μAt the point of intersection, the
x,
y, and
z coordinates must be equal.
Equating
x-coordinates:
3+λ=4+2μ⇒λ−2μ=1Equating
z-coordinates:
1−λ=4+2μ⇒λ+2μ=−3Adding the two equations:
(λ−2μ)+(λ+2μ)=1+(−3)2λ=−2⇒λ=−1Substitute
λ=−1 into
λ+2μ=−3:
−1+2μ=−3⇒μ=−1Put
λ=−1 in the first line:
x=3+(−1)=2,y=5+2(−1)=3,z=1−(−1)=2So the point of intersection is
(2,3,2).
This satisfies both lines, hence it is the correct point.
Answer:Option A:
(2,3,2)