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Question
For solving pair of equation, in this exercise use the method of elimination by equating coefficients :
3 - (x - 5) = y + 2
2 (x + y) = 4 - 3y
Solution
3 - (x - 5) = y + 2
∴ 3 - x + 5 = y + 2
∴ - x + 8 = y + 2
∴ x + y = 6 ....(1)
2( x + y ) = 4 - 3y
∴ 2x + 2y = 4 - 3y
∴ 2x + 5y = 4 .....(2)
Multiplying equation no (1) by 2.
2x + 2y = 12 .....(3)
Subtracting equation (2) from (3)
2x + 2y = 12
- 2x + 5y = 4
- - -
- 3y = 8
y = - `8/3`
From (1)
x - `8/3` = 6
⇒ x = `26/3`
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