If 2^x + y = 4^8, what is the value of y

If 2^x + y = 4^8, what is the value of y?

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Nha Ha

First simplify the equation so that 4 has the same base as 2. Then you have x+y = 16.

From here you can use the given statements to find that the answer is B.

Dec 29, 2015 • Comment

Cydney Seigerman, Magoosh Tutor

Yes, great set-up! As you said, we can rewrite 4^8 so that the two expressions have the same base of 2:

2^(x+y)
4^8 = (2^2)^8 = 2^16

From there, we have 2^(x+y) = 2^16 and therefore x+y=16.

Dec 30, 2015 • Reply

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