Question

Does (4,5) represent a solution to the equation x+y+z=9?

Answer 1

Yes

Explanation:

you substitute 4 for x and 5 for y.

4 + 5 + z = 9

z = 0

so when you plug all of it together it equals 9.

Answer 2

1) no, because a solution must be an ordered triple pair (x,y,z)

2) { x+y+z=5

{ 2x-3y+z=7

{ x+2y-4z=2

3) infinity many solutions

4) use equations (1) and (2) to eliminate y

5) solve one equation for one of its varaibles

Explanation:

should be 100% on the quick check if you put those answers