Question

Consider this system of linear equations:

y − x = -13
-4x + 3y = -51

Answer 1

choices (-12,1) (-12,-1) (12,-1)

Answer 2

Hi! I think I can help you with this :)

Answer 3

First of all, any ideas about how to get started, or are you completely stuck?

Answer 4

im completelty stuck on the lesson its self :(

Answer 5

Okay, no problem!

Answer 6

ok

Answer 7

I can think of two possible ways to answer this question. One way would be to try and solve the equations yourself. Alternatively, we could just try each of the multiple choice answers and see which one works.

Answer 8

mines say 0,0

Answer 9

Any preference?

Answer 10

im thinking that it is -12,1

Answer 11

Id start with adding x to both sides
y − x +x= -13+x
y=-13+x
The subtitute the y value in place of 3y
-4x + 3(-13+x) = -51 <---solve for x

Answer 12

that looks confusing

Answer 13

Not at all :)
\[\huge~\rm~-4x + 3(-13+x) = -51 \]
Distribute the 3
\[\huge~\rm~ 3(-13+x) \]

Answer 14

-39+3x

Answer 15

Good
-39+3x
\[\huge~\rm~-4x -39+3x = -51 \]
Combine like terms

Answer 16

im confused

Answer 17

See the x's ? Combine them since they are like terms -4+3=?

Answer 18

-1x

Answer 19

Good now add
−x−39+39=−51+39
-51+39=?

Answer 20

-12

Answer 21

right?

Answer 22

its just 12

Answer 23

no bevause 51 is negative.

Answer 24

a negative divided by a negative is a postivie

Answer 25

but its not divided its added

Answer 26

Answer what i asked you
-51+39=?

Answer 27

-12