Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
MightySmurf
Group Title
Solve this system of equations using the addition method.
3xy=9
2x+y=6 Solve this system of equations using the addition method.
3xy=9
2x+y=6 @Mathematics
 3 years ago
 3 years ago
MightySmurf Group Title
Solve this system of equations using the addition method. 3xy=9 2x+y=6 Solve this system of equations using the addition method. 3xy=9 2x+y=6 @Mathematics
 3 years ago
 3 years ago

This Question is Closed

conheomap Group TitleBest ResponseYou've already chosen the best response.3
5x + 0 = 15 x = 3 plug to the first equation 2.3 + y = 6 y = 0
 3 years ago

MightySmurf Group TitleBest ResponseYou've already chosen the best response.0
so i would just add the numbers then divide
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
first add the equation 1 and 2 so that it will get rid of one of the variable In this example, you got it easy because in equation 1 you have y, and in equation 2 you have y, so the sum of these equations will get rid of y
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
in case you want to get rid of x first. then you would have to do the following: multiply 1st equation by 2 multiply 2nd equation by 3 so that it would appear like this 6x .... 6x  0x ......
 3 years ago

MightySmurf Group TitleBest ResponseYou've already chosen the best response.0
im sorry im very confused..see im takin algebra online and dnt have a teacher so i have to take tests online and have no idea how to do them
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
ok so you have two equations and two variables which is x, y. They ask you to find those values of x, y so that when you plug them in to any equation, they have to be true. In this case if you plug x = 0 and y = 3. Both equations hold. That's how it goes anyways.
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
Now they asked you to use addition method which means. some how you have to add equation 1 and equation 2
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
3xy=9 + 2x+y=6  5x + 0 = 15 the new equation only has x now. So you know what x is, just plug into any of the equations they gave you, you will get y value.
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
give me another problem, i'll explain in more details because this is problem is very simple.
 3 years ago

MightySmurf Group TitleBest ResponseYou've already chosen the best response.0
ok 4a5b=7 4a+5b=17
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
alright. this is also simple. Let's change to 4a + 5b = 7 2a + 3b = 9 instead.
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
now what do you do? I want to know how you do it, then I'll explain
 3 years ago

MightySmurf Group TitleBest ResponseYou've already chosen the best response.0
i add 4a to 2a right
 3 years ago

MightySmurf Group TitleBest ResponseYou've already chosen the best response.0
then i add5b and3b
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
ok. but the new equation doesn't get rid of any variables right? so your stuck
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
you have to modify the original equations somehow so when adding you will get either 0x or 0y
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
look at this problem you gave me: 4a5b=7 4a+5b=17 notice the 5b (1st) and 5b (2nd equation). when adding the result is 0b. that's why i said they gave you a simple problem. Just adding.
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
did you learn how to modify the equations yet? or just purely adding stuff?
 3 years ago

MightySmurf Group TitleBest ResponseYou've already chosen the best response.0
no did learn to modify the equations
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
okay then please try to modify this one: 4a + 5b = 7 2a + 3b = 9
 3 years ago

MightySmurf Group TitleBest ResponseYou've already chosen the best response.0
i cnt i dnt understand how to modify im sorry
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
let's try to modify so when adding I will get 0a ok?
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
i see first equation have 4a. the 2nd have 2a. ... I need to have some how to have 2nd equation to have 4a. Right?
 3 years ago

MightySmurf Group TitleBest ResponseYou've already chosen the best response.0
ummm yes
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
you can do this by multiply 2nd equation by 2
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
what's the modified equation now?
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
ok the modified (2nd equation) becomes: 4a 6b = 18
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
now you can add the first and the modified.
 3 years ago

MightySmurf Group TitleBest ResponseYou've already chosen the best response.0
so then id add the 4a and 5b
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
no no. it's gonna be like this: 4a + 5b = 7 + 4a 6b = 18  0a b = 11
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
you only add the a and a... b and b not a and b.
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
so now you can solve for the b value. Once you have one variable solved, plug to any of the original equation, then bam. That's it
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
can you modify to get rid of b instead of a this time? it's a bit harder, but same method. 4a + 5b = 7 2a + 3b = 9
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
you have to modify both equations for b.
 3 years ago

MightySmurf Group TitleBest ResponseYou've already chosen the best response.0
4a+2a right
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
yes what about b
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
so you will get 6a + 8b = 16?
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
it doesn't get rid of b does it?
 3 years ago

MightySmurf Group TitleBest ResponseYou've already chosen the best response.0
so i subtract
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
you need to get help from professor about this. But those problems you gave me. you can just add them directly without modifying anything.
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
you are not clear about the concept of adding.
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
one thing I can tell you that when adding you must get rid of one of the variables.
 3 years ago

MightySmurf Group TitleBest ResponseYou've already chosen the best response.0
no im not im sorry thnks for tryin to help tho
 3 years ago

conheomap Group TitleBest ResponseYou've already chosen the best response.3
i have to go home. sorry
 3 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.