Question

Can I get some help?

Answer 1

Given the system of equations presented here:

4x + y = 4
2x + 7y = 28

Which of the following actions creates an equivalent system such that, when combined with the other equation, one of the variables is eliminated?

Multiply the second equation by −1 to get −2x − 7y = −28
Multiply the second equation by −4 to get −8x − 28y = −112
Multiply the first equation by −7 to get −28x − 7y = −28
Multiply the first equation by −2 to get −8x − 2y = −8

Answer 2

You lost me at the systems of equations.

Answer 3

If you were to add the two equations together (to solve by eliminating a variable), you want the coefficients of one variable to cancel out. So, if you have +5x in one equation, you want to have -5x in the other. Add those together, and you have no more x.

Answer 4

So which option would eliminate a variable?

Answer 5

I have no idea @BTaylor

Answer 6

For each answer, you'd have:
1) 4x + y = 4 & −2x − 7y = −28
2) −8x − 28y = −112 & 2x + 7y = 28
3) −28x − 7y = −28 & 2x + 7y = 28
4) −8x − 2y = −8 & 2x + 7y = 28.
Which one would eliminate a variable?

Answer 7

when you multiply
2x + 4y = 14
by 2 you get
4x + 8y = 28

Answer 8

the result of this is
4x + 8y = 28
4x + y = 20

Answer 9

@jackmullen10 that doesn't get you anywhere.

Answer 10

how so?

Answer 11

It's a multiple choice question. What you did doesn't eliminate any variables. It isn't even one of the options.

Answer 12

then you simplify subtract 4x and y now you have

Answer 13

i wasnt done

Answer 14

oh i see

Answer 15

i misread the question

Answer 16

well then it would be c im pretty sure because its asking which one would eliminate a variable and be subtracting by 7y you would cross out the y variable.