How do you solve 0.5^x=16^20.5x=162?

1 Answer
Sep 8, 2016

x = -8x=8

Explanation:

When you are working with equations with indices, try to

either rarr " make the bases the same" make the bases the same

or rarr " make the indices the same" make the indices the same

0.5 = 1/20.5=12 This is a better form to use, because you should recognise that 16 is one of powers of 2.......

rarr2^4 = 16 and 2^8 = 16^224=16and28=162

(1/2)^x = 16^2(12)x=162

(1/2)^x = 2^8(12)x=28

2^-x = 2^8 " " rarr "one of the index laws: "(a/b)^m = (b/a)^-m2x=28 one of the index laws: (ab)m=(ba)m

Now the bases are the same so we have:

-x = 8 hArr x = -8x=8x=8