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log7(3-x)=2log7(4) equation

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Numerical solution:

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The solution

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log(3 - x)     log(4)
---------- = 2*------
  log(7)       log(7)
$$\frac{\log{\left(3 - x \right)}}{\log{\left(7 \right)}} = 2 \frac{\log{\left(4 \right)}}{\log{\left(7 \right)}}$$
Detail solution
Given the equation
$$\frac{\log{\left(3 - x \right)}}{\log{\left(7 \right)}} = 2 \frac{\log{\left(4 \right)}}{\log{\left(7 \right)}}$$
$$\frac{\log{\left(3 - x \right)}}{\log{\left(7 \right)}} = \frac{2 \log{\left(4 \right)}}{\log{\left(7 \right)}}$$
Let's divide both parts of the equation by the multiplier of log =1/log(7)
$$\log{\left(3 - x \right)} = 2 \log{\left(4 \right)}$$
This equation is of the form:
log(v)=p

By definition log
v=e^p

then
$$3 - x = e^{\frac{2 \log{\left(4 \right)} \frac{1}{\log{\left(7 \right)}}}{\frac{1}{\log{\left(7 \right)}}}}$$
simplify
$$3 - x = 16$$
$$- x = 13$$
$$x = -13$$
The graph
Rapid solution [src]
x1 = -13
$$x_{1} = -13$$
x1 = -13
Sum and product of roots [src]
sum
-13
$$-13$$
=
-13
$$-13$$
product
-13
$$-13$$
=
-13
$$-13$$
-13
Numerical answer [src]
x1 = -13.0
x1 = -13.0