Hello, checkmarks!

First, find the equation of the plane.1. The line of intersection of the planes:

If meets the -plane at point and the -axis at point

determine the length of line segment

We have: .

And we have: .

Substitute into [2]: .

We have these equations: .

On the right, replace with a parameter

These are the parametric equations of the line of intersection.

Line intersects the -plane at . . . Then: .

Then

. . We have point

Line intersected the -axis at . . . Then: .

Then: .

. . We have point

Therefore, length of