Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
liizzyliizz
Group Title
Solve using elimination.
5x + 2y = 7
10x + 4y = 14
ok so I am reteaching myself algebra 2, and I was doing this, would there be no solution? I am not sure If I did this correct.
 2 years ago
 2 years ago
liizzyliizz Group Title
Solve using elimination. 5x + 2y = 7 10x + 4y = 14 ok so I am reteaching myself algebra 2, and I was doing this, would there be no solution? I am not sure If I did this correct.
 2 years ago
 2 years ago

This Question is Closed

jim_thompson5910 Group TitleBest ResponseYou've already chosen the best response.0
let z = 5x+2y
 2 years ago

jim_thompson5910 Group TitleBest ResponseYou've already chosen the best response.0
double both sides 2z = 2(5x+2y) 2z = 10x+4y
 2 years ago

jim_thompson5910 Group TitleBest ResponseYou've already chosen the best response.0
so if 5x + 2y = 7 10x + 4y = 14 then we can also say z = 7 2z = 14 where z = 5x+2y
 2 years ago

jim_thompson5910 Group TitleBest ResponseYou've already chosen the best response.0
but....what happens when we solve 2z = 14 for z?
 2 years ago

liizzyliizz Group TitleBest ResponseYou've already chosen the best response.0
I am not sure If I am thinking about this in the correct way, but technically wouldn't z would = 7. and we already know that. So I am a bit lost now, with where you're going with this.
 2 years ago

jim_thompson5910 Group TitleBest ResponseYou've already chosen the best response.0
2z = 14 > z = 7 but z = 7 in the first equation
 2 years ago

jim_thompson5910 Group TitleBest ResponseYou've already chosen the best response.0
so no matter what happens, we're going to get z = 7
 2 years ago

jim_thompson5910 Group TitleBest ResponseYou've already chosen the best response.0
so because z = 5x+2y, this means that 5x+2y = 7 and this applies to both equations because the two are really the same equation
 2 years ago

Mertsj Group TitleBest ResponseYou've already chosen the best response.2
The problem says to solve by elimination so multiply the first equation by 2 and then add the two equations. You will get the true statement 0=0 which tells you that there is an infinite number of solutions.
 2 years ago

liizzyliizz Group TitleBest ResponseYou've already chosen the best response.0
oh ok, I got the 0=0 but I wasnt sure if that meant infinite or no solutions. which is why I said no solutions. Ahh thank you for that clarification.
 2 years ago

Mertsj Group TitleBest ResponseYou've already chosen the best response.2
If you got a nonsense statement such as 0 = 3, that would indicate no solution.
 2 years ago

liizzyliizz Group TitleBest ResponseYou've already chosen the best response.0
that makes more sense, I feel so silly now for confusing that.
 2 years 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.