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Solve the system of equations by elimination.

-5x - 2y = 41

2x + 2y = - 26

User Dr Nic
by
7.1k points

1 Answer

3 votes

Answer:

x = -5

y = -8

Explanation:

-5x - 2y = 41

2x + 2y = - 26

We can treat these two equations as if we're adding them.

Note** Positive plus negative (or negative plus positive) is subtraction

Starting with the X's

-5x + 2x = -3x

Y's

-2y + 2y = 0... 0, meaning the Y's have faced elimination. They are no longer in the equation

Numbers

41 + -26 (adding a negative, so subtraction)...

41-26 = 15

Now that we have everything, let's put it together

-3x = 15

Now dividing by -3 to get the X alone, you get

X = -5

Since we have X, we can use either equation that was originally in the question to solve for Y. Let's use the first one.

-5x - 2y = 41

-5(-5) -2y = 41

25-2y=41

-2y = 16

y= -8

Let's use the other one too just to prove

2x + 2y = - 26

2(-5) + 2y = -26

-10+2y=-26

2y = -16

y= -8

User Peter Kirchner
by
7.3k points