Question

Solve by elimination:

Answer 1

Answer:

B (5, 13)

Step-by-step explanation:

9x + 4y = 97

9x + 6y = 123

To solve by elimination, we want to eliminate a variable. To do this, we must make one variable cancel out.

First, we can see that both equations have 9x. To cancel out x, we must make one of the 9x's negative. To do this, multiply each term in the equation by -1.

-1(9x + 6y = 123)

-9x - 6y = -123

This is one of your equations. Set it up with your other given equation.

9x + 4y = 97

-9x - 6y = -123

Imagine this is one equation. Since every term is negative, you will be subtracting each term.

9x + 4y = 97

-9x - 6y = -123

___________

0x -2y = -26

-2y = -26

To isolate y further, divide both sides by -2.

y = 13

Now, to find x, plug y back into one of the original equations.

9x + 4(13) = 97

Multiply.

9x + 52 = 97

Subtract.

9x = 45

Divide.

x = 5

Check your answer by plugging both variables into the equation you have not used yet.

-9(5) - 6(13) = -123

-45 - 78 = -123

-123 = -123

Your answer is correct!

(5, 13)

Hope this helps!