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Solve the system of equations using elimination: 3x+3y=0 and -7x-9y=18

User Poles
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1 Answer

3 votes

Answer:

x = 9, y = -9

Explanation:

To solve the system of equations:

3x + 3y = 0

-7x - 9y = 18

We can use the method of substitution. Rearranging the first equation, we get:

3x = -3y

Dividing both sides by 3, we get:

x = -y

Now we can substitute this expression for x into the second equation:

-7(-y) - 9y = 18

Simplifying, we get:

7y - 9y = 18

-2y = 18

Dividing both sides by -2, we get:

y = -9

Now that we know y, we can substitute this value back into either of the original equations to find x. Using the first equation, we get:

3x + 3(-9) = 0

Simplifying, we get:

3x - 27 = 0

Adding 27 to both sides, we get:

3x = 27

Dividing both sides by 3, we get:

x = 9

Therefore, the solution to the system of equations is:

x = 9, y = -9

User Aran Freel
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