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Question
For solving pair of equation, in this exercise use the method of elimination by equating coefficients :
2x - 3y - 3 = 0
`[2x]/3 + 4y + 1/2` = 0
Solution
2x - 3y - 3 = 0
⇒ 2x - 3y = 3 .....(1)
`[2x]/3 + 4y + 1/2` = 0
Multiply by 6,
`6 xx [2x]/3 + 6 xx 4y + 1/2 xx 6 = 0 xx 6`
4x + 24y = - 3 .....(2)
Multiplying equation no. (1) by 8
16x - 24y = 24 .....(3)
Adding equation (3) and (2)
16x - 24y = 24
+ 4x + 24y = - 3
20x = 21
x = `21/20`
From (1)
∴ `2[21/20]` - 3y = 3
∴ - 3y = 3 - `21/20`
∴ y = `-3/10`
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