Question

Question 7

Solve the following system of equations by using the elimination method.
-4x – 2y = -12
4x + 8y = -24

(5, 3)

(-6, -6)

(3, 1)

(6, -6)

Answer 1

To solve this problem you must apply the proccedure shown below:

1. You have the following system of equation:

$\left \{ {{-4x-2y=-12} \atop {4x+8y=-24}} \right.$

2. As you can see, you can cancel out the variable $x$, because it has equal coefficient with different signs at both equations. Then, if you add both equations, you obtain:

$6y=-36\\y=-6$

3. Let's substitute the value obtained into the second equation to calculate the other variable:

$4x+8(-6)=-24\\4x-48=-24\\x=6$

The answer is: (6,-6).