SOLUTION: 2log[base 3](x+4)-log[base 3]9=2

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Question 415755: 2log[base 3](x+4)-log[base 3]9=2
Found 2 solutions by ewatrrr, stanbon:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi







  3^2 = (x+4)^2/9

  81= (x+4)^2

 ± 9 = x + 4

  -4 ± 9 = x   (x = -13 is an Extraneous solution)

   x = 5

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
2log[base 3](x+4)-log[base 3]9=2
-----
2log3(x+4) - log3(9) = 2
---
log3[(x+4)^2/9] = 2
----
(x+4)^2/9 = 3^2
(x+4)^2 = 81
---
x^2+8x+16-81 = 0
---
x^2 + 8x - 55 = 0
---
x = [-8 +- sqrt(64-4*-55)]/2
----
x = [-8 +- sqrt(284)]/2
---
x = [-8 +- 2sqrt(71)]/2
---
x = -4+sqrt(71) or x = -4-sqrt(71)
==================
Cheers,
Stan H.
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