Question

using the addition method,solve each system of equations

using the addition method,solve each system of equations

x+y=-3
x= 1

Answer 1

ok for this one all you need to go is plug 1 in for x so you will have

1+y=-3

now subtract the one to the other side

and y=-4

Answer 2

got there now what

Answer 3

isn't this the substitution method???

Answer 4

yes now dont i have to find x

Answer 5

ohh wait we already got x its 1 lol

Answer 6

no your objective was to find y

so y=-4

now you can plug it back into the equation and you get: 1+-4=-3

and that is true

Answer 7

i got the check done.. can you help me with a few more like these sorta

Answer 8

yes :)

Answer 9

k here it is 3x - 5y=8
5y=10

Answer 10

3x - 5y=8
5y=10

Answer 11

Ok so this is how we set the problem up

3x-5y=8
5y=10

now we add downwards, so the y cancels out because -5y+5y= 0
and then we have to add 8+10 which equals 18

so now we have

3x=18

divide 3 by both sides and you are left with x=6

now for the fun part :)

since we know x now, we can simply plug it into the top part of the problem

3x-5y=8

plug in 6 for x and we have

3(6)-5y=8

that is really just

18-5y=8

now we subtract 18 from both sides

and we have: -5y=-10

if we divide -5 by -10
we get 2

so y=2

plugging all this into the equation

3x-5y=8

3(6)-5(2)= 8

and this is true :)

Answer 12

thank you so much!.. can you help me with like two more questions like this

Answer 13

yah do you want me to explain everything again, or just show you the steps quickly? Do you understand how to do it?

Answer 14

2x+6y=5
2x-3y=-4

Answer 15

just show me the steps sorta like what u just did but with less words and if i need help ill post heere if i need help

Answer 16

okay!

Answer 17

2x+6y=5
2x-3y=-4

ok for this problem theres nothing we can make zero right away so we have to multiply by two to get the -3y to -6y so then we can subtract. make sure to multiply by 3 for EVERY variable

2x+6y=5
4x-6y=-8

6x=-3
x=-.5

now we can plug in the x in either equation it doesnt matter

2(-.5)+6y=5

-1+6y=5
6y=6

y=1

check:

4(-.5)-6(1)=8

Answer 18

sorry thats a -8***

Answer 19

thanks. i need help with a few more if your okay with helping

Answer 20

can you try them on your own and show me where you need help?

Answer 21

wait the equation is not correct
cause when u go to check it doesnt fit back in and equal the correct answer

Answer 22

yes it does
4(-.5)=-2
6(1)=6

-2-6=-8

Answer 23

oh okay.. can you work through this one with me
x+2y=9
3x-2y=7

Answer 24

can you please try it first on here and show me what you dont understand

Answer 25

4x=16
x=4

4+2y=9
2y=5
y=5/2

Answer 26

so u ad 3x +x and got 4x

Answer 27

yes!

Answer 28

but then you replace 4 from the x to make 4+2y=9

Answer 29

then what do u do with that 4

Answer 30

subtract it from 9 because you want the y's on one side

Answer 31

oohhh

Answer 32

Does this all make sense, do you have any questions?

Answer 33

i have one more problem like this but how would u do the check for this one

Answer 34

x+2y=9

(4)+2(5/2)=9

Answer 35

wait i got it :) i need help walkin me through one more like u just did

Answer 36

okay can i see you try it for me please!

Answer 37

yes and can u help me if i get stuck

Answer 38

of course, thats our job here at openstudy :)

Answer 39

x+3y=11
x+3y=7

Answer 40

u would add 3+3 right to make 6

Answer 41

x=8

Answer 42

no you cant do that you want to cancel a letter (variable) out
so you need to multiply

Answer 43

grrr

Answer 44

so what would be the easiest to do

Answer 45

ugh these are the trickier ones, wait one second well I get my book

Answer 46

okay

Answer 47

this problem appears like it is a substitution one

Answer 48

no its an addition method one

Answer 49

x+3y=11
x+3y=7

Answer 50

do i have to solve that? I can only show the steps

Answer 51

use addition method

Answer 52

multiply the 2nd equation by -1 and add them

Answer 53

that would cancel everything out

Answer 54

Actually obviously there are no solutions there.. x+3y cannot equal to 11 and 7 at the same time.

Answer 55

it's inconsistent, or whatever u call it.

Answer 56

yah that is what i thought

Answer 57

thanks :)

Answer 58

Kk here we go:

x+y=-3
x= 1

You can look at this as:

x+y=-3
x+0y= 1

You can then add the negative:

x + y = -3
+ - (x + 0y = 1)


Which is:

x + y = -3
+ -x = -1
------------
0 + y = -4

Answer 59

You already know what x =, because that's part of your two initial equations. Now you know that y = -4, as well, and you've solved the system.

Answer 60

Lol. Never mind, looks like the question evolved from that to something else...

Answer 61

im confused

Answer 62

no that will not work for x+3y=11

Answer 63

This problem is inconsistent therefore there is not an anwer that will solve both at the same time

Answer 64

think about it, its the same variables so they can only equal one number not two at the same time

Answer 65

okay so it cant be workable..

Answer 66

correct :)

Answer 67

thank you so much for your help..