I need help with Fractional Equations and Extraneous Solutions?

Question

The question is 1/5-1/20=1/x ? im lost so anything would help..

Answer 1

1/5 = 4/20

So this equation could simply be rewritten:

4/20 -1/20 = 1/x
(4 - 1)/20 = 1/x
3/20 = 1/x

To find x, simply flip both sides of this equation over:

20/3 = x/1 = x

Answer 2

Well...

1/5-1/20=1/x

Divide 1 by both sides to obtain

1/(1/5 - 1/20) = 1/(1/x) which is

x = 1/(1/5-1/20)
= 1/(4/20 - 1/20)
= 1/(3/20)
= 20/3