Question 701038
(1)/(3)X + (1)/(5)Y =7

(1)/(6)X - (2)/(5)Y = -4
using elimination method. 
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Your parentheses don't contribute anything.
1/3X + 1/5Y =7
1/6X - 2/5Y = -4
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I'll assume you mean:
(1/3)X + (1/5)Y =7
(1/6)X - (2/5)Y = -4
See the difference?
It clarifies that the x & y is not in the denominator.
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(1/3)X + (1/5)Y = 7 times 15 --> 5x + 3y = 105
(1/6)X - (2/5)Y = -4 time 30 --> 5x -12y = -120
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5x + 3y = 105
5x -12y = -120
-------------- Subtract
15y = 225
y = 15
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x = 12