3x+5y=0 and x+4y+-7

i need help on these simultaneous equations!
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1 Answer

3x + 5y = 0

x + 4y = -7

multiply the bottom equation by -3

3x + 5y = 0

-3x - 12y = 21

add the equations together

0x - 7y = 21

-7y = 21

y = -3

3x + 5(-3) = 0

3x - 15 = 0

3x = 15

x = 5

Answer:  x = 5, y = -3
by Level 13 User (103k points)

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