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(a) The total value of a two digit number is 10x + y
(b) Let the number be xy
3(x + y) =(10 + y) + 8
3x + 3y = 10x + y + 8
7x - 2y = 8
The reversed number is yx
Therefore 10y + x - 10x - y = 9
9y -9x = 9
9(7x -2y = 8)
2(-9x + 9y= 9)
63x - 18y = 72
-18x + 18y = 18
45x = 90
x = 2
7x - 2y = 8
14 - 2y = 8
2y = 6
y = 3
The number is 23
raphael answered the question on January 24, 2017 at 05:13
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