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3 years ago

X+y=20 3x-3y=30 Which values of x and y satisfy this system of equations?

Mathematics

1 answer:

puteri [66]3 years ago

4 0

x +y = 20 ( rewrite as x = 20-y)

3x - 3y =30

3(20-y) - 3y = 30

60-3y - 3y = 30

60-6y = 30

-6y = -30

y = -30 / -6 = 5

x=20-5 = 15

x = 15, y = 5

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