Question

2x - y = 10
4x + 2y = 20

Answer 1

2x - y = 10 (× 2)
4x + 2y = 20

4x - 2y = 20
4x + 2y = 20
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8x = 20
x = 20 ÷ 8
x = 5

2 × 5 - y = 10
10 - y = 10
y = 0

s={5, 0}