Hi there,

Can someone please show me how to solve the following equation:

5^x + 25^(2x) = 150

Any help will be greatly appreciated,

Cheers

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- Nov 13th 2007, 08:36 PMtazrulz99Adding algebraic exponents
Hi there,

Can someone please show me how to solve the following equation:

5^x + 25^(2x) = 150

Any help will be greatly appreciated,

Cheers - Nov 13th 2007, 09:26 PMjanvdl
Hmm, just check that you didn't make a typo somewhere, it does look a bit like a hard equation for pre-algebra i would say.

$\displaystyle 5^x + 25^{2x} = 150$

$\displaystyle 5^x + 5^{4x} = 150$

$\displaystyle Set \ 5^x = k$

$\displaystyle k + k^4 = 150$

$\displaystyle k^4 + k - 150 = 0$

I quickly solved it by drawing a graph (See the attached image)

And it seems the answers are**-3,54**and**3.46** - Nov 13th 2007, 09:34 PMtazrulz99.
Ok and from there you solve with logs. Thanks!

- Nov 13th 2007, 09:46 PMjanvdl