Hi

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ABcoordinates are (-3,3,-4)

Therefore one parametric equation of l is :

x = -3t + 1

y = 3t -2

z = -4t +3

C(x,y,z) is on the plane iff 2x+y-3z=9

C is on l iff there exists t such that

x = -3t + 1

y = 3t -2

z = -4t +3

Substitute x,y,z in the Cartesian equation of the plane to get one linear equation. Solve for t and substitute in x,y,z expressions.

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