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How would you do this help-example-1
User Dephinera
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1 Answer

9 votes

Answer:

Multiply the second equation by 2

Solution:
(-(45)/(11),(29)/(11))

Explanation:

1) In order to use the elimination method to solve systems of equations, you must first multiply one or both of the equations so that the coefficients of a pair of terms with matching variables share the same number, but have opposite signs.

In this case, the y terms must fit that requirement. The y term in the first equation is 2y and the one in the second equation is -y. They already have opposite signs, one positive and other negative, so we just need -y to be -2y. So, in order to do that, multiply by 2.

2) After multiplying the whole second equation by 2, you will get
8x - 2y = -38. Now, add the the two equations together, eliminate the y terms, and isolate x to find its value.

3) Then, substitute that x value back into one of the equations to receive the y-value.

To better explain these steps, I attached pictures below.

How would you do this help-example-1
How would you do this help-example-2
How would you do this help-example-3
User Glynn Bird
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4.5k points