Question:
Which equation does the graph of the systems of equations solve ?
Option A:−1/3x + 3 = x − 1
Option B: 1/3x − 3 = −x + 1
Option C: −1/3x + 3 = −x − 1
Option D: 1/3x + 3 = x − 1
Answer:
Option B:
![(1)/(3)x-3=-x+1](https://img.qammunity.org/2021/formulas/mathematics/college/agufm4c768cuextw646yx5pz769dx5qsxm.png)
Solution:
Option A:
![(-1)/(3)x+3=x-1](https://img.qammunity.org/2021/formulas/mathematics/college/ikfp3gd6ul2tp86u2bl0ts8zvuh71h4sfb.png)
Add 1 on both sides of the equation.
![(-1)/(3)x+4=x](https://img.qammunity.org/2021/formulas/mathematics/college/idr02s3ybb2554zid6q5jf0whce042idwa.png)
Add
on both sides of the equation.
![4=(4)/(3)x](https://img.qammunity.org/2021/formulas/mathematics/college/68wr3522u03iqxm44rhewv7qmd0rwdy0as.png)
Multiply by 3 on both sides.
12 = 4x
Divide by 4.
x = 3
Substitute this in x – 1, we get
y = 3 – 1 = 2
(3, 2) is not a solution.
Option B:
![(1)/(3)x-3=-x+1](https://img.qammunity.org/2021/formulas/mathematics/college/agufm4c768cuextw646yx5pz769dx5qsxm.png)
Add 3 on both sides of the equation.
![(1)/(3)x=-x+4](https://img.qammunity.org/2021/formulas/mathematics/college/4qr2msg5r9akuago7x22cnu0qkjv65y347.png)
Add x on both sides of the equation.
![(4)/(3)x=4](https://img.qammunity.org/2021/formulas/mathematics/college/w4haldldkczdhev810fc2qdxz5ew3s6rau.png)
Divide by 4.
x = 3
Substitute this in –x + 1, we get
y = –3 + 1 = –2
(3, –2) is a solution.
Option C:
![(-1)/(3)x+3=-x-1](https://img.qammunity.org/2021/formulas/mathematics/college/u7eqg5wd3d1sny65a5mkxpt4olu3iadyen.png)
Subtract 3 on both sides of the equation.
![(1)/(3)x=-x-4](https://img.qammunity.org/2021/formulas/mathematics/college/9r8kfrdib3vzxnlim38rq45i6p831fe3h1.png)
Add x on both sides of the equation.
![(4)/(3)x=-4](https://img.qammunity.org/2021/formulas/mathematics/college/2uwlam71tl10rb6mdx8cyn7z9ubjr4e5pz.png)
Divide by 4.
x = –3
Substitute this in –x – 1, we get
y = –3 – 1 = –4
(3, –4) is not a solution.
Option D:
![(1)/(3)x+3=x-1](https://img.qammunity.org/2021/formulas/mathematics/college/xndcw1ohdptecn1xgshnttgtmy6hfu5yxl.png)
Add 1 on both sides of the equation.
![(1)/(3)x+4=x](https://img.qammunity.org/2021/formulas/mathematics/college/awayhua1czbo4jha0ybnmmjnq9xzqryyvc.png)
Subtract
on both sides of the equation.
![4=(2)/(3)x](https://img.qammunity.org/2021/formulas/mathematics/college/ovy3t786f6mu0fw0bk1cmwy37bix20bnn6.png)
Multiply by 3 on both sides.
12 = 2x
Divide by 2.
x = 6
Substitute this in x – 1, we get
y = 6 – 1 = 5
(6, 5) is not a solution.
Hence Option B is the correct answer.
The equation of the graph of the system of equations is
.