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3 votes
Substitute

X+y=3y

2x+4y=14

1 Answer

7 votes
answer: x = 7/2 y = 7/4

first u need to choose a variable. i’ll choose x because it’s easy to isolate.

x + y = 3y
x = 2y

substitute:

2x + 4y = 14
2(2y) + 4y = 14
4y + 4y = 14
8y = 14
y = 7/4

then u can find x by substituting back in

2x + 4y = 14
2x + 4(7/4) = 14
2x + 7 = 14
2x = 7
x = 7/2

answer:

y = 7/4
x = 7/2


hope this helps :)
User Shane Bishop
by
4.7k points