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log10(x)*20=-15 equation

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Numerical solution:

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The solution

You have entered [src]
 log(x)         
-------*20 = -15
log(10)         
$$20 \frac{\log{\left(x \right)}}{\log{\left(10 \right)}} = -15$$
Detail solution
Given the equation
$$20 \frac{\log{\left(x \right)}}{\log{\left(10 \right)}} = -15$$
$$\frac{20 \log{\left(x \right)}}{\log{\left(10 \right)}} = -15$$
Let's divide both parts of the equation by the multiplier of log =20/log(10)
$$\log{\left(x \right)} = - \frac{3 \log{\left(10 \right)}}{4}$$
This equation is of the form:
log(v)=p

By definition log
v=e^p

then
$$x = e^{- \frac{15}{20 \frac{1}{\log{\left(10 \right)}}}}$$
simplify
$$x = \frac{\sqrt[4]{10}}{10}$$
The graph
Rapid solution [src]
     4 ____
     \/ 10 
x1 = ------
       10  
$$x_{1} = \frac{\sqrt[4]{10}}{10}$$
x1 = 10^(1/4)/10
Sum and product of roots [src]
sum
4 ____
\/ 10 
------
  10  
$$\frac{\sqrt[4]{10}}{10}$$
=
4 ____
\/ 10 
------
  10  
$$\frac{\sqrt[4]{10}}{10}$$
product
4 ____
\/ 10 
------
  10  
$$\frac{\sqrt[4]{10}}{10}$$
=
4 ____
\/ 10 
------
  10  
$$\frac{\sqrt[4]{10}}{10}$$
10^(1/4)/10
Numerical answer [src]
x1 = 0.177827941003892
x1 = 0.177827941003892