how to solve equations with variables as exponents?

• Oct 11th 2010, 08:35 AM
yolanda
how to solve equations with variables as exponents?
What steps would I have to do to solve an equation such as 2 x 3 = 7 x 5^x and 4.6 x 1.06^(2x + 3) = 5 x 3^x

if you could answer in the simplest way you can it would be greatly appreciated. :)
• Oct 11th 2010, 08:41 AM
Jhevon
Quote:

Originally Posted by yolanda
What steps would I have to do to solve an equation such as 2 x 3 = 7 x 5^x and 4.6 x 1.06^(2x + 3) = 5 x 3^x

if you could answer in the simplest way you can it would be greatly appreciated. :)

use logarithms, do you know how?

btw, using "x" for variables and multiplication signs (which is what i think you're doing) is a bad idea.
• Oct 11th 2010, 09:23 AM
yolanda
I don't know how, which is why I asked
• Oct 11th 2010, 09:47 AM
consider
a^x = b
(write it on paper)
we can make b the subject, which is above
we can make a the subject, which will be: a = b^(1/x)
however, to make x the subject there is a notation: logs

so x is the power by which we raise a to get b.
the notation is logab=x
note: the a is subscript

So make 5^x the subject first
so assuming u got 5^x = s, where s is a number
so x is the power by which we raise 5 to get s
ie x=log5s

Now u can use an advanced calculator
• Oct 11th 2010, 12:13 PM
yolanda
:'( i hate math
• Oct 11th 2010, 12:15 PM