(ii) 4x + 3y – 4 = 0; 6x = 8 – 5y
Sol. 4x + 3y – 4 = 0
∴ 4x + 3y = 4
6x = 8 – 5y
∴ 6x + 5y = 8
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D
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=
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4
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3
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=
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(4 × 5) – (6 × 3)
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=
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20 – 18
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=
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2
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6
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5
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DX
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=
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4
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3
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=
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(4 × 5) – (8 × 3)
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=
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20 - 24
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=
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- 4
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8
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5
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DY
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=
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4
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4
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=
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(4 × 8) – (6 × 4)
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=
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32 - 24
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=
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8
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6
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8
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By Cramer's rule,
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x
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=
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Dx
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=
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-4
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=
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-2
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D
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2
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y
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=
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Dx
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=
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8
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=
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4
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D
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2
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x = - 2 and y = 4 is
the solution of given simultaneous equations.
