Question

-10x-3y=7 2x-2y=-4 solve using elimination show steps

Answer 1

First we stack them.

-10x-3y=7
2x-2y=-4
—————
Next we need to get rid of one of the variables so if we multiply the bottom equation by 5 we can make 2x become 10x

-10x-3y=7
10x-10y=-20
——————- Now we can subtract to only have the y value
-13y=27
Divide -13 to both sides
Y=-2.0769 now we can plug in the y value into one of the equations

2x-2(-2.0769)=-4
2x+4.1538=-4
-4.1538 -4.1538
———————————
2x=-0.1538
——————-
0.0769=x. (0.0769,-2.0769)

Answer 2

The solution is the ordered pair (-1,1)

Explanation:

-10x -3y = 7

2x - 2y = -4 → multiply through by 5 10x -10y = -20

Ad d the two bold equations together

-10x - 3y = 7

10x - 10y = -20

-13y = -13 Divide both sides by -13

y = 1 Substitute 1 for y in either of the two original equations to solve for x

2x - 2y = -4

2x - 2(1) = -4

2x -2 = -4 Add 2 to each side

2x = -2 Divide both sides by 2

x = -1

The solution is the ordered pair (-1,1)