2. Solve the following simultaneous equations by using
Cramer's rule:
3x – y = 7 & x
+ 4y = 11
Answer. The given equations are 3x – y = 7 & x + 4y = 11
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D
=
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3
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-1
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=
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(3
× 4) – (1 × - 1)
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=
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12
+ 1
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=
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13
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1
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4
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Dx
=
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7
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-1
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=
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(7×
4) – [11× (-1)]
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=
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28
+ 11
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=
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39
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11
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4
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Dx
=
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3
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7
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=
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(3×11)
– [1× 7]
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=
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33
- 7
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=
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26
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1
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11
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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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39
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=
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3
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D
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13
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y
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=
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Dy
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=
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26
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=
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2
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D
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13
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