SOLUTION: x 3(2 )=42

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Question 149962: x
3(2 )=42

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
3%282%5Ex%29=42 Start with the given equation.


2%5Ex=14 Divide both sides by 3.


log%2810%2C%282%5Ex%29%29=log%2810%2C%2814%29%29 Take the log of both sides.


x%2Alog%2810%2C%282%29%29=log%2810%2C%2814%29%29 Rewrite the left side using the identity log%28b%2C%28x%5Ey%29%29=y%2Alog%28b%2C%28x%29%29


x=log%2810%2C%2814%29%29%2Flog%2810%2C%282%29%29 Divide both sides by log%2810%2C%282%29%29.


x=log%282%2C%2814%29%29 Use the change of base formula to rewrite the right side.



So the answer is x=log%282%2C%2814%29%29 which approximates to x=3.81