Question

If $4^{x+y}$ = 256 and $(256{)}^{x-y}$, = 4 then what is the value of x and y?

• A. 17/8, 15/8
• B. 17/4, 15/4
• C. 9/17, 15/17
• D. 8/17, 8/15
• E. None of the above

Answer 1

The correct option is A 17/8, 15/8

$4^{x+y}$ = 256 $\Rightarrow$ x + y = 4

$(256{)}^{x-y}$ = 4 $\Rightarrow$ x - y = $\frac{1}{4}$

Solving, we get y = 15/8 and x=17/8