Question

yoyoyoyoyoyo please help ???????!?!?!?!?!


Use the substitution method to solve the following system of equations:

3x + 5y = 3
x + 2y = 0

(1, 1)

(6, −3)

(6, 1)

(1, −3)

Answer 1

Ok, well first, pick a variable to isolate (x, or y).

Answer 2

We'll do this for the second equation since it's a bit easier.

Answer 3

y ? @iambatman

Answer 4

Yeah sure, that works, so now we want to isolate it as you would a normal equation. Since we're dealing with x+2y=0

Can you get y on the left side on your own?

Answer 5

wait how do i solve it?

Answer 6

x+2y=0
subtract x from both sides

x+2y=0
-x -x

2y = -x

now divide both sides by 2

y= -x/2

Does that make sense?

Answer 7

Next thing you want to do is take that expression and substitute it into equation 1 (where the y is).

Answer 8

3x + 5(-x/2) = 3

like that?

Answer 9

Yes :)

Answer 10

Now what's 3x - 5x/2?

Answer 11

ill brb

Answer 12

Ok back, did you make any progress? 3x - 5x/2, treat as you would as if it's a regular fraction, what's 3-5/2 =?

Answer 13

i got -1

Answer 14

3-5/2?

Answer 15

Try again, :S

Answer 16

3-5=-2
-2/2
-1?

Answer 17

What? it's 5/2..like

\[3-\frac{ 5 }{ 2 }\] fraction.

Answer 18

what? how do i solve that?

Answer 19

At this point in your math career, I'd assume you would know fractions :\

Answer 20

3/1 - 5/2 ?

Answer 21

yes!

Answer 22

its 1/2

Answer 23

Yes so 3x-5x/2 = x/2

Answer 24

\[\frac{ x }{ 2}=3\]

solve for x

Answer 25

x=6?

Answer 26

Yes

Answer 27

Now you have x, now we take that expression pick one of the equations 1 or 2, lets pick 2 since it's a bit easier again,

x+2y=0 we solved x = 6 so sub that into the equation

6+2y=0

solve for y now.

Answer 28

y=-3?

Answer 29

@iambatman

Answer 30

Yes :D, good job!