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May 5, 2016
Posted by **Jeconiah** on Tuesday, August 7, 2012 at 3:23am.

- Please help quick!! Mathematics A -
**Elena**, Tuesday, August 7, 2012 at 5:26am(3^2)^x-3^x-8=0,

(3^x)² -3^x -8 = 0,

3^x =y,

y² -y - 8=0,

y= (1±√33)/2.

Since 3^x>0, the negative root is nonsence,

=> y= (1+√33)/2 =3.37228,

3^x =3.37228,

x=log(3)3.37228= =ln3.37228/ln3≈1.21559/1.0986=1.1065

Test:

9^1.1065 – 3^1.1065 – 8 =

=11.372 – 3.372 – 8 = 0