73, because when you simply it all adds up and make sense
About 142ish i think. sorry if it's not the answer you were looking for.
The circumference is pi times the diameter of the circle. The radius is half of the diameter. In this case, the radius is then 36.
Y' = -2x+a
0 = -2(3)+a
6=a
8=-(3)^2 +(3)(6)+b
b=-1
The property the applies only to addition and multiplication is the commutative property. It means that the numbers can be arranges in any order. so for example you will get the same answer whether you do
5+6 or 6+5