If the line, `(x-3)/2=(y+2)/(-1)=(z+4)/3` lies in the plane, `l x+m y-z=9` , then `l^2+m^2` is equal to: (1) 26 (2) 18 (3) 5 (4) 2

Explanation

Given line is `(x-3)/2 = (y+2)/-1 = (z+4)/3`

So, point `P(3,-2,-4)` lies on the given plane `lx+my-z = 9`

`:. 3l-2m+4 = 9`

`=>3l-2m = 5->(1)`

Now, direction ratios of the line and direction ratios of the plane will be perpendicular.

So, their product is `0`.

`:.2l-m-3 = 0=>2l-m = 3->(2)`

so, multiplying (2) with `2` and subtracting it from (1),

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