00:01
We want a line perpendicular to this plane, 2x -3y -z.
00:05
I'm going to write this in standard form real quick.
00:09
2x -3y -z, 0, through the point 1, 3, 7.
00:17
We can get the normal vector to this plane is 2, negative 3, negative 1.
00:28
So our line is going to start off with a parameterization of 2t -3t -t.
00:34
Excuse me.
00:36
Plus it needs to go through this point 1, 3, 7.
00:39
So just plop in 1, 3, 7 right there, and we get 2t plus 1, negative 3t plus 3, negative t plus 7.
00:49
Bada bing, bada boom, there's part a.
00:53
Part b, where does the line cut the plane? well, we want to solve for where all the x, y, z where this happens, right? so let's plug this in.
01:06
2 times the x component of our line is 2t plus 1, minus 3 times our y component is negative 3t plus 3, minus our z component is negative t plus 1, and this should be equal to 0.
01:25
I'm expanding things out here.
01:28
4t plus 2 plus 9t minus 9 plus t minus 1, right? and then we can combine our t stuff here.
01:40
4 plus 9 plus 1 times t plus 2 minus 9 minus 1 is equal to 0...