how do I use the substitution method to solve 2x+4y= -3 2x-y=7

Question

must use the substitution method to solve this system. answer for both x and y.

Answer 1

RONG WAE ("method")

line 1...2x+4y=-3

line 2...2x-y=7

line1 -line2...(2x-2x)+(4y+y)=(-3-7)

5y=-10

y=-2

from line 2, 2x=y+7...7-2...5

x=5/2=2.5

Answer 2

Given 2x+4y= -3......(1)
2x-y=7.......(2)

Using substitution method
from equation (2)
y=2x-7 in equation (1)
2x+4(2x-7)= -3
x=5/2

Substitute in equation (2)
2(5/2)-y=7
y=-2

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