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 :-)
I think it would be 72+4x=400
400-72= 328
328/4= 82
So the answer would be 82=x
$10.00 - 3($0.65)
$10.00 - $1.95
= $8.05
60x1.15=69
Retail price is $69