<PRE><B>Question 279400</B>
{{{drawing(400,214.2857143,-1,13,-1,10,
locate(12.2,4.5,9), locate(6,5.8,15),
triangle(0,0,12,0,12,9), locate(7,0,x) )}}}
&lt;pre&gt;&lt;font size = 4 color = &quot;indigo&quot;&gt;&lt;b&gt;
We need to find x by the Pythagorean theorem:

(bottom leg)&lt;sup&gt;2&lt;/sup&gt; + (right leg)&lt;sup&gt;2&lt;/sup&gt; = (hypotenuse)&lt;sup&gt;2&lt;/sup&gt;

                     x&lt;sup&gt;2&lt;/sup&gt; + 9&lt;sup&gt;2&lt;/sup&gt; = 15&lt;sup&gt;2&lt;/sup&gt;

                     x&lt;sup&gt;2&lt;/sup&gt; + 81 = 225

                          x&lt;sup&gt;2&lt;/sup&gt; = 225 - 81

                          x&lt;sup&gt;2&lt;/sup&gt; = 144

                           x = 12

So the perimeter is 15 + 9 + 12 = 36  

Edwin&lt;/pre&gt;</PRE>