126k views
1 vote
Beyonce is solving a system of equations:

2x-3y=-2 and 4x+y=24
She multiplies the second equation by 3 and then adds the first equation to find 14x=-70, showing her that x=5. Beyonce finds that y=4. Thinking about this process, Beyonce says out loud,
“There are lots of ways I could go about solving this problem. I could do the method above or I could multiply the first equation by -2 and add the second. I seem to find that there is only one solution to the two equations but I wonder if I will get the same solution if I use a different method?
1. What is the answer to Beyonce's question? Be sure to show work or explain reasoning.


2. Is the answer to (a) different if we have a system of two equations with no solutions? What if there are infinite solutions?

1 Answer

4 votes

Answer:

x=5, y=4. (5, 4).

Explanation:

2x-3y=-2

4x+y=24

------------------

-2(2x-3y)=-2(-2)

4x+y=24

----------------------

-4x+6y=4

4x+y=24

--------------

7y=28

y=28/7

y=4

4x+4=24

4x=24-4

4x=20

x=20/4

x=5

User Bitz
by
4.5k points