Question 1086634
<pre>

{{{6/x-4}}}{{{"">""}}}{{{-1}}}

One way is to plug them all in and see:

Plug in 20 

{{{6/20-4}}}{{{"">""}}}{{{-1}}}

{{{-3.7}}}{{{"">""}}}{{{-1}}}

False.

Plug in 19 

{{{6/19-4}}}{{{"">""}}}{{{-1}}}

{{{-3.684210526}}}{{{"">""}}}{{{-1}}}

False.

Plug in 18 

{{{6/18-4}}}{{{"">""}}}{{{-1}}}

{{{-3.666666667}}}{{{"">""}}}{{{-1}}}

False.

Plug in 17 

{{{6/17-4}}}{{{"">""}}}{{{-1}}}

{{{-3.647058824}}}{{{"">""}}}{{{-1}}}

False.

Edwin</pre>