Here is the triangle. Let b represent the base.
Then since the legs are 4 cm longer than b, they are
b+4 each:
The perimeter is just the measurement all the way around the RIM
of of the triangle. [Notice that the word "RIM" is inside the word
"peRIMeter"].
Perimeter = LEFT LEG + RIGHT LEG + BASE = 44cm. So
(b+4) + (b+4) + b = 44
b + 4 + b + 4 + b = 44
3b + 8 = 44
-8 -8
--------------
3b = 36
=
b = 12
So the base is 12cm.
Edwin