Question

Solve using elimination 5x-4y=-21 -2x+4y=18

Answer 1

Answer:

x=-1, y=4

Step-by-step explanation:

When we solve by elimination, we are getting rid of one variable, in this case y.  We will add the two equations together.

5x-4y=-21

-2x+4y=18

---------------

3x  = -3

Divide each side by 3

3x/3 =-3/3

x =-1

Now we need to calculate y

-2x +4y = 18

Substitute x=-1

-2(-1)+4y = 18

2+4y =18

Subtract 2 from each side

4y = 18-2

4y=16

Divide each side by 4

4y=16/4

y =4