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Elimination using multiplication. What is the best answer for this?? 2x-3y=21

5x-2y=25

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Answer:

x=3 and y=-5

I eliminated the y variable so I found the least common factor between 2 and 3 which is 6. I multiplied the first equation by 2 and the second equation by -3 (it's a negative 3 because in order to eliminate the variable, they need to have opposite signs.) That gives me a result of:

4x-6y=42

-15x+6y=-75

Now you can eliminate the y variables and just add the equations together to get:

-11x=-33

x=3

Then plug the x back into one of the original equations to find your y.

2(3)-3y=21

6-3y=21

-3y=15

y=-5

Finally always check your answers by plugging them into the other equation that you did not use

5(3)-2(-5)=25

15+10=25

25=25

Hope this helps!

User Robert White
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