# Math

posted by
**Kellie**
.

I have 2 problems I need help with both I have narrowed it down to 2 possible answers but can't decide which one is right. The first problem log subscript 5 (2x+3)=2 the choices a)13/2 and b) 14. The next problem 8^x = 16^x+2 the choices a)8 and b)-8. Help please!

If log5 z = 2 then z=25

2x+3=25 x=you do it.

8^x = 16^(x+2)

8^x = 2^x+2 * 8^x+2

divide by 8^x

1=64*2^(x+2)

1/64 = 2^(x+2)

1/2^6 = 2^(x+2)

2^-6 = 2^(x+2)

now take the log base 2 of each side.