log7(3-x)=2log7(4) equation
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The solution
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
$$3 - x = 16$$
$$- x = 13$$
$$x = -13$$
Sum and product of roots
[src]
$$-13$$
$$-13$$
$$-13$$
$$-13$$