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Question
For solving pair of equation, in this exercise use the method of elimination by equating coefficients :
41x + 53y = 135
53x + 41y = 147
Solution
41x + 53y = 135 ...(1)
53x + 41y = 147 ...(2)
Adding equation (1) and (2)
41x + 53y = 135
+ 53x + 41y = 147
94x + 94y = 282
Dividing by 94,
x + y = 3 ....(3)
Subtracting equation (2) from (1)
41x + 53y = 135
- 53x + 41y = 147
- - -
- 12x + 12y = - 12
Dividing by 12,
- x + y = -1 ....(4)
Adding (3) and (4)
x + y = 3
+ - x + y = -1
2y = 2
y = 1
From (3)
x + y = 3
x + 1 = 3
x = 2
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