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Equation
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y = 2x + 6 ------------------ (1)
3x - y = 6 -------------------(2)
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Substitute equation (1) into (2)
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3x - (2x + 6) = 6
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Remove bracket
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3x - 2x - 6 = 6
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Combine like terms
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x - 6 = 6
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Add 6 to both sides
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x = 6 + 6
x = 12
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Substitute x = 12 into equation (1)
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y = 2 (12) + 6
y = 24 + 6
y = 30
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Answer : x = 12, y = 30
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