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3 years ago

Find the solution set of x + y = 5, 2 x - y = 7

1 answer:

4 0

X + y = 5
x = 5 - y

2x - y = 7
2(5-y) - y = 7
10 - 2y - y = 7
10 - 3y = 7
10 - 7 = 3y
3 = 3y
y = 1

x + y = 5
x + 1 = 5
x = 5 - 1
x = 4

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Given that,

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Below is an attachment containing the solution.

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