The answer is 3. Would you like me to explain it?
Stop asking questons we are pretty much telling you the answer figure it out your self
Answer:
a) As sides of squares are always equal.
So,
BC=CD
2b+CF=a+b
CF= a+b-2b
CF= a-b
b) Area of rectangle CDEF= CDxCF
=(a+b)(a-b)
=(a²-b²)
Hope it helps :-)