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# Help: exponential function equations step by step

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1. 516-(x2-x) = 25 - (x2-8)​ The "2" numbers are exponents (bn)
2. 254x = 1/5x2

Please, I really need help.

Oct 18, 2017
edited by chaconsara32  Oct 18, 2017

#1
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Hard to read the frst one but I assume this is :

1. 516 -(x^2 - x)  =  25-(x^2 - 8)   simplify as

5 -x^2 + x + 16  =  (52) 8 - x^2

5 -x^2 + x + 16  =  516 -x^2

Since the bases are the same.....solve for the exponents

-x^2 + x + 16   =   16  - x^2    subtract x^2 from both sides

x + 16  =  16       subtract 16 from both sides

x  = 0   Oct 18, 2017
#2
+1

Yes, it is like that I still need to get the hang of writing these on a computer! Thanks!

chaconsara32  Oct 18, 2017
edited by chaconsara32  Oct 18, 2017
#3
+2

Here's the second one

254x  = (1/5)x^2

Note that 1/5  =  5^-1    and 25  = 5^2 ....so we have....

(5^2)4x =  (5^-1)x^2

58x =  5-x^2    the bases are the same....solve for the exponents

8x  = -x^2     add x^2 to both sides

x^2 + 8x  = 0      factor

x ( x + 8)  = 0       set both factors to 0  and solve for x and we get that

x = 0    or   x  = -8   Oct 18, 2017
#4
+1

Thank you very much for your help! (☞ﾟヮﾟ)☞ ☜(ﾟヮﾟ☜)

chaconsara32  Oct 18, 2017