Question

Jordan wants to solve the following system using the elimination method:

2x + 3y = 10
x + y = 7

What number should the equation x + y = 7 be multiplied by to eliminate y?

−2
2
−3
3

I think it is 2 can someone help me to see if I am correct

Answer 1

Its either 3 or -3.

Answer 2

@payeton12 why do you think so, cna you explain? ;)

Answer 3

In the first equation, we have 3y. In the second equation we have y.

If we multiply the second equation by 3, then if we subtract both the equations, we will be able to eliminate y.

If we multiply the second equation by -3, then if we add both the equations, we will be able to eliminate y.

The answer to your question is: 3 and -3.

Answer 4

Depends if your adding or subtracting.

Answer 5

@AloneS

Answer 6

in this case I think we are adding

Answer 7

it is not 3 so I am taking it is -3

Answer 8

it's a lousy question, because you can either add or subtract the equations.
if you know you are adding, then you want the 3y in the top equation to be added to a -3y in the bottom equation (because 3y + -3y is zero)

Answer 9

I am not as good as you think I am if I knew what you are telling me phi I would've not asked the question