Question

Determine an equation for the line of intersection of the planes 5x+y+2z+15=0 and 4x+y+2z+8=0

Answer 1

@eLg or anyone who can help me:)

Answer 2

use elimination

Answer 3

i did, i got x=-7, then I tried to subs. in the equation I got y=20-2z.. then i'm stuck

Answer 4

the answer is y=20, z=0, i got x right

Answer 5

did you substitute it in the equation where there is only y and z variables?

Answer 6

which equation?

Answer 7

substitute the variable again until you have an equation for y and z only

Answer 8

y=20-2z.

Answer 9

@eLg

Answer 10

oh ok thanks!