Question

Solve the system using elimination 7x+2y=10 -7x+y=-16

Answer 1

7x + 2y = 10

-7x + y = -16

Since one equation has a 7x and and the other equation has a -7x,

when we add the equations together, the x's will cancel out.

So we have 3y = -6 and y = -2.

To find x, plug -2 back in for y in either of the two original equations.

I've chosen to plug -2 into the first equation to get 7x + 2(-2) = 10.

Solving from here, x = 2.

So our final answer is the ordered pair (2, -2).

Now, check your answer.

Answer 2

x=2, y=-2

Explanation:

7x+2y=10

-7x+y=-16

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0x + 3y = -6

Divide each side

3y/3 = -6/3

y = -2

Now find x

7x +2y = 10

7x + 2( -2) = 10

7x -4 = 10

Add 4 to each side

7x -4+4 = 10+4

7x= 14

Divide by 7

7x/7 = 14/7

x = 2