Question

The following system is solved by substitution. Which expression is substituted for z in the second and third equations?

x + 5y – z = 6
3x – y – 2z = 4
3x – 2y + 3z = 13

a. x + 5y + 6
b. x + 5y – 6
c. –x – 5y + 6
d. –x – 5y – 6

Answer 1

The question is asking you to solve for z in eqn 1. Can you do that?

Answer 2

i dont know how to

Answer 3

x + 5y – z = 6

that is the first equation. Solving for z means that we want z to be by itself. One thing we can do is to add z to both sides.

Can you do that?

Answer 4

x + 5y = z + 6

Answer 5

Great now we want to subtract 6 from both sides

x + 5y = z + 6

x + 5y-6 = z + 6-6

x + 5y-6 = z

Can you tell me which answer has this expression
x + 5y-6

Answer 6

answer choice B

Answer 7

good job