Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
Use the substitution method to solve the following system of equations.
x + 2y – z = 7
4x – y + 3z = –2
2x + 2y – z = 9
 one year ago
 one year ago
Use the substitution method to solve the following system of equations. x + 2y – z = 7 4x – y + 3z = –2 2x + 2y – z = 9
 one year ago
 one year ago

This Question is Closed

ZeldaBest ResponseYou've already chosen the best response.2
Well, here we go: First let's set the first equation equal to: – z = 7  x  2y Which becomes: z = x+2y  7 okay?
 one year ago

ZeldaBest ResponseYou've already chosen the best response.2
No put this in equation #2: 4x – y + 3z = –2 Becomes: 4x – y + 3(x+2y  7) = –2 Which becomes: 4x  y +3x +2y 21 = 2
 one year ago

ZeldaBest ResponseYou've already chosen the best response.2
So, then we combine like terms to get: 4x  y +3x +2y 21 = 2 7x + y 21 = 2 y = 7x +19 And finally put this in the third equation and solve for x. So put in the first and second equations into the third one and solve for x.
 one year ago

ZeldaBest ResponseYou've already chosen the best response.2
So we have z = x+2y  7 and we have y = 7x +19 SO in the third equation: 2x + 2y – z = 9 Wherver you see a z, put that equation, and where you see a y, put in the equation for y. (First put in the y in the z equation)
 one year ago
See more questions >>>
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.