Show that the lines and
intersect and find their point of intersection.
Given: - Two lines equation: and
To find: - Intersection point
We have,
⇒ x = λ, y = 2λ + 2 and z = 3λ – 3
So, the coordinates of a general point on this line are
(λ, 2λ + 2, 3λ – 3)
The equation of the 2nd line is
⇒ x = 2μ + 2, y = 3μ + 6 and z = 4μ + 3
So, the coordinates of a general point on this line are
(2μ + 2, 3μ + 6, 4μ + 3)
If the lines intersect, then they must have a common point.
Therefore for some value of λ and μ, we have
⇒ λ = 2μ + 2 , 2λ + 2 = 3μ + 6, and 3λ – 3 = 4μ + 3
⇒ λ = 2μ + 2 ……(i)
⇒ 2λ – 3μ = 4 ……(ii)
and 3λ – 4μ = 6 ……(iii)
putting value of λ from eq i in eq ii, we get
⇒ 2(2μ + 2) – 3μ = 4
⇒ 4μ + 4 – 3μ = 4
⇒ μ = 0
Now putting value of μ in eq i, we get
⇒ λ = 2μ + 2
⇒ λ = 2(0) + 2
⇒ λ = 2
As we can see by putting value of λ and μ in eq iii, that it satisfy the equation.
Check
⇒ 3λ – 4μ = 6
⇒ 3(2) = 6 ;Hence intersection point exist or line do intersects
We can find intersecting point by putting values of μ or λ in any one general point equation
Thus,
Intersection point
λ, 2λ + 2, 3λ – 3
⇒ 2, 6, 3