What is the solution of x+y=2 and 2x+5y=16

1 answer:

8 0

X+ y = 2....multiply by -2
2x + 5y = 16
--------------
-2x - 2y = -4 (result of multiplying by 2-)
2x + 5y = 16
-------------add
3y = 12
y = 12/3
y = 4

x + y = 2
x + 4 = 2
x = 2 - 4
x = -2

solution is (-2,4)

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as expected.

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