<PRE><B>Question 336572</B>
From a rectangle , corner is cut in triangular shape to give a pentagon .
 The length of the sides are 13,19,20,25 and 31 in cm . lengths are not in order
 . find the area of the pentagon.
:
I assigned the dimensions as follow: 
starting with the hypotenuse of the triangle = 13
the remaining part of that side = 19
bottom = 25
vert side = 31
top = 20
:
Find the area of the rectangle without the triangle removed
25 * 31 = 775
:
The triangle dimensions: 5 by 12 by 13, 
prove it is a right triangle: {{{sqrt(5^2+12^2)}}} = 13
A = .5 * 5 * 12 = 30
:
Pentagon area: 775 - 30 = 745</PRE>