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4 votes
Use logarithms to solve each equation

2x 9/8=111
A. 18.9561
B.25.8961
C. 10.2587
D. 35.5208

User Ulak Blade
by
7.2k points

1 Answer

6 votes
We have this equation:


2x^{(9)/(8)} = 111

and we need to find the value of x.

First of all, we multiply the whole equation for 1/2, so our goal is to isolate x, therefore:


x^{(9)/(8)}=(111)/(2)

Next step we must do is to apply logarithms:


logx^{(9)/(8)} = log((111)/(2))

Next, we have to apply identities and then to solve the equation:


(9)/(8)logx = log((111)/(2))

logx = (8)/(9)log((111)/(2))

logx = 1.5504

10^(logx) = 10^(1.5504)

Finally, we have the value of x which was our goal. This is the answer for the question above:


x= 35.5140

The answer is D.
User EvAlex
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8.4k points