Question

Solve by the substitution method please
7x+y=-13
-5x+y=17
what is the order pair?

Answer 1

I have tried to work it out myself and this is what I got.
-5x+y(-7x-13)=17
So I going with x=-35/7 which gave me -5 so that is my x but I can get my y= yet. I tried and gt 22/20 thats not right?????

Answer 2

Your process seemed right, but I got x to be -5/2

Answer 3

Also realize there is no y once you substitute it into that one equation, I think you just had a typo though.

Answer 4

but -5/2 is 2.5

Answer 5

the 22/20 is what I got

Answer 6

for y

Answer 7

For y I got 9/2. Now you can check these numbers if you plug them into one of the equations and both sides are equal.

Answer 8

So can you help me with it again

Answer 9

Yes. So it looks like you tried to solve the first equation for y to get y=-7x-13 Then it looked like you plugged it into the 2nd equation and should have gotten -5x+(-7x-13)=17

Answer 10

All you need to do next is solve for x, plug it back into one of the equations and solve for y.

Answer 11

so when I do that then I get 13y+17/7y+5 and the whole problem is negative with a neg.sign front understand

Answer 12

I don't quite see what you are doing...-5x-7x-13=17 then -12x=30 then x=-5/2 so plug -5/2 into either of the equations to get y. So for example, -5(-5/2)+y=17 then (25/2)+y=17 and y=9/2

Answer 13

ok so what is the order pair

Answer 14

can you please give me the order pair to this question

Answer 15

(x,y) so (-5/2,9/2) which is the same as (-2.5,4.5)

Answer 16

so that is the order pair?

Answer 17

Yes. If you plug in both the x and y into either of those equations you should get the left side equal to the right.

Answer 18

thanks again, is there a program that helps you work these out and learn them

Answer 19

Not sure...

Answer 20

so I need to put (-2.5,4.5) in or (-5/2, 9/2) in

Answer 21

Yes.

Answer 22

when I put in the first one it said incorrect!!!

Answer 23

The answers are correct based on the equations you gave me. I promise.

Answer 24

sorry the top one is suppose to be 4y sorry so 7x+4y=-13 and -5x+y=17 I am so sorry I could not figure out what I was doing wrong

Answer 25

Lol no problem, but that does change things :P

Answer 26

http://www.webmath.com/solver2.html here is something I found that does solve systems of equations, well at least 2 of them. I looked over their work, and it seems like it can be confusing. I would recommend trying to do them on your own solving for x or y like we did, and maybe using that website to check steps if you made a mistake. There's probably something better out there somewhere.

Answer 27

So can I get the order pair for this then please and I can move on to the next.....please...

Answer 28

x=-3 y=2 so (-3,2)

Answer 29

i have to continue working on ths because I am still a little confused but trying to understand. Thanks for the help again....I have more to come....

Answer 30

No problem.