(1) 5x + 3y = 15

Clearly insufficient.

(2) y = 5 – (5/3)x

Solve:

y/5= 1-x/3

x/3+y/5=1

therefore

5x+3y=15

This equation is same as equation 1)

So equation 1 and equation 2 are same and insufficient. So E

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