Aw yis
take the coefients and put them in rows
![\left[\begin{array}{ccc}4&5&|-7\\3&-6&|24\end{array}\right]](https://tex.z-dn.net/?f=%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%265%26%7C-7%5C%5C3%26-6%26%7C24%5Cend%7Barray%7D%5Cright%5D%20)
divide 2nd row by 3
![\left[\begin{array}{ccc}4&5&|-7\\1&-2&|8\end{array}\right]](https://tex.z-dn.net/?f=%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%265%26%7C-7%5C%5C1%26-2%26%7C8%5Cend%7Barray%7D%5Cright%5D%20)
multiply 2nd row by -4 and add to top one
![\left[\begin{array}{ccc}0&13&|-39\\1&-2&|8\end{array}\right]](https://tex.z-dn.net/?f=%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D0%2613%26%7C-39%5C%5C1%26-2%26%7C8%5Cend%7Barray%7D%5Cright%5D%20)
divide top row by 13
![\left[\begin{array}{ccc}0&1&|-3\\1&-2&|8\end{array}\right]](https://tex.z-dn.net/?f=%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D0%261%26%7C-3%5C%5C1%26-2%26%7C8%5Cend%7Barray%7D%5Cright%5D%20)
multiply top row by 2 and add to bottom row
![\left[\begin{array}{ccc}0&1&|-3\\1&0&|2\end{array}\right]](https://tex.z-dn.net/?f=%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D0%261%26%7C-3%5C%5C1%260%26%7C2%5Cend%7Barray%7D%5Cright%5D%20)
x=2
y=-3
Im pretty sure it is D
hope you get this right
A function has only one y-value for each x-value. If you find a set that has an x-value used more than once, it is not a function, because that x-value is now paired with more than one y-value.
The fourth answer is the only one that has the same x-value used more than once.
Side note: Don’t worry if a y-value is used more than once. That’s totally fine. It’s all about the x-values.