Given the system of equations presented here:

2x + 4y = 14
4x + y = 20

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

A. Multiply the second equation by −4 to get −16x − 4y = −80
B.Multiply the second equation by −1 to get −4x − y = −20
C.Multiply the first equation by 2 to get 4x + 8y = 28
D.Multiply the first equation by −1 to get −2x − 4y = −14

Question

Given the system of equations presented here:

2x + 4y = 14
4x + y = 20

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

A. Multiply the second equation by −4 to get −16x − 4y = −80
 B.Multiply the second equation by −1 to get −4x − y = −20
 C.Multiply the first equation by 2 to get 4x + 8y = 28
  D.Multiply the first equation by −1 to get −2x − 4y = −14

mehek14 · Answer

Multiply the first equation by 2
so when you subtract 4x - 4x
x is eliminated

anonymous · Answer

ok Can you show me step by step i am really confused.

mehek14 · Answer

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

mehek14 · Answer

now you have 
4x + 8y = 28
4x + y = 20

anonymous · Answer

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