How do you solve $\frac{1}{5} - \frac{1}{20} = \frac{1}{x}$ $1/5-1/20=1/x$ and find any extraneous solutions?

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Answer 1 · 2016-05-26T20:13:51

$x = - 15$ $x=-15$

The equation is 'undefined' for $x = 0$ $x=0$ . You are mathematically 'not allowed' to divide by 0

However, the equation structure is such that the value of $x$ $x$ is fixed at a value other than 0

Turn everything upside down giving

$x = 5 - 20 = - 15$ $x=5-20 =-15$

How do you solve 15−120=1x1/5-1/20=1/x and find any extraneous solutions?