Question 965840
Find the vertex half-angle using the height and side. 
{{{cos(V/2)=1.5/2.5}}}
{{{cos(V/2)=0.6}}}
{{{V/2=53.13}}}
{{{V=106.26}}}
The other two angles are found using the sum of the angles,
{{{X+X+V=180}}}
{{{2X=73.74}}}
{{{X=36.87}}}
Then use the law of sines to find the other side. 
{{{sin(106.26)/Y=sin(36.87)/2.5}}}
{{{Y=2.5*(sin(106.26)/sin(36.87))}}}
{{{Y=4}}}
So the perimeter would be,
{{{P=2.5+2.5+4}}}
{{{P=9}}}{{{ft}}}