SOLUTION: Solve. Round any approximate solution to the fourth decimal place. 3^2r x 3^r-4=97 Please show me step by step to get the answer. Thanks

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: Solve. Round any approximate solution to the fourth decimal place. 3^2r x 3^r-4=97 Please show me step by step to get the answer. Thanks      Log On


   

Question 475935: Solve. Round any approximate solution to the fourth decimal place.
3^2r x 3^r-4=97
Please show me step by step to get the answer. Thanks
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
3%5E%282r%29%2A+3%5E%28r-4%29=97
Formula x%5En%2Ax%5Ek=x%5E%28n%2Bk%29
3%5E%282r%2B%28r-4%29%29=97
3%5E%282r%2Br-4%29=97
3%5E%283r-4%29=97 take the logarithm of both sides of the equation by the base 3
3r-4=log%283%2C97%29, use scientific calculator for log%283%2C97%29=4.16408
3r-4=4.16408 add 4 to the both sides
3r=8.16408 divide by 3
r=2.7214