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Question
By equating coefficients of variables, solve the following equations.
3x - 4y = 7; 5x + 2y = 3
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Solution
3x - 4y = 7 ...(I)
5x + 2y = 3 ...(II)
Multiply (II) with 2
10x + 4y = 6 ...(III)
Adding (I) and (III)
3x - 4y = 7
10x + 4y = 6
13x = 13
⇒ x = 1
Putting the value of x in (I) we get
∴ 3x - 4y = 7
⇒ 3 × 1 - 4y = 7
⇒ 3 - 4y = 7
⇒ y = -1
Thus, x = 1 and y = -1
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