Question

I really need help with systems of equations!
3x+4y=8
-2x+5y=3 (I need to find x and y)

Answer 1

First add both equations together. Let me know what you get afterwards.

Answer 2

what do you mean add them?

Answer 3

oh I got it! ok one sec

Answer 4

-5x+9y=11?

Answer 5

You added 3 and -2 and got 5?

Answer 6

Doesn't 3 + (-2) = 1

Answer 7

yeah yeah, sorry. so 1x+9y=11?

Answer 8

Yes or simply

x + 9y = 11

Answer 9

Now, with this form, what we can do next is isolate x by subtracting 9y from both sides to get

x = 11 - 9y

Answer 10

ok :)

Answer 11

Now we can just simply substitute the expression 11 - 9y for x in to one of the original equations.

Answer 12

3(11 - 9y) + 4y = 8

Answer 13

At this point, you can solve for y

Answer 14

y=29/27?

Answer 15

Can you show your work please?

Answer 16

actually I did it with a calculator haha sorry, I didnt want to seem dumb. I´ll try though

Answer 17

You got y = 29/27 from a calculator? Are you sure?

Answer 18

yeah, an online calculator

Answer 19

anyways Ill try to do it step by step

Answer 20

Either that calculator isn't working properly or you input the equation incorrectly.

Answer 21

3(11-9y)=8-4y

Answer 22

(11-9y)=4/3y?

Answer 23

Not exactly. Why would you divide both sides by 3 instead of distributing the 3?

Answer 24

Do you remember distributive property?

a( b + c) = ab + ac
3(11 - 9y) = ?

Answer 25

3(11-9y)=4?

Answer 26

thank you for your patience, I am the worst at math I know

Answer 27

y=25/23 ? @Hero

Answer 28

y = 25/23 but I'm more interested in the steps you took to get that.

Answer 29

I thought you left, thats why I just wanted to quickly check with you if it was the right answer before you left

Answer 30

so 3(11-9y)=4?

Answer 31

It is not possible to remove the y from the 4 without justification. I don't understand what you believe you're trying to accomplish here. What happened to distributing the 3?

Answer 32

I dont understand either haha. ok so if we have 3(11-9y)+4=8, what would be the next step?

Answer 33

The original equation was

3x + 4y = 8 correct?

Answer 34

yes.

Answer 35

And we already solved for x and got 11 - 9y correct?

Answer 36

yes.

Answer 37

So if we remove x from 3x + 4y = 8 and replace it with 11 - 9y, we get

3(11 - 9y) + 4y = 8

Answer 38

The next step is to distribute the 3

Answer 39

thats the part where i am stuck, how do I distribute it?

Answer 40

3(11 - 9y) = 33 - 27y

Answer 41

ok, so 3(11-9y)=6y?

Answer 42

@hero?