4/9 cm^2 and I hope the picture explains it
The greatest comment factor of 28 and 64 is 4.
The factors of 28 are 28, 14, 7, 4, 2, 1.
The factors of 64 are 64, 32, 16, 8, 4, 2, 1.
The common factors of 28 and 64 are 4, 2.
the greatest one of the two factors is 4.
It would take them a half and hour
This is known as the commutative property of addition.
Hope this helps!
