Answer: the answer is 180 
Step-by-step explanation:
Area of a rectangle multiply length times base. 15 x 12 = 180. Hope this helps!
Answer:
40 square units
Step-by-step explanation:
First of all, lets say that square has side
, so, the area unit is 
the diagonal's square is 
CALCULATION OF TRIANGLES'S AREA (there are 4 triangles)

CALCULATION OF MAIN SQUARE AREA

TOTAL AREA

This sequence has generating function

(if we include
for a moment)
Recall that for
, we have

Take the derivative to get


Take the derivative again:


Take the derivative one more time:


so we have
