Answer:
x
=
40
Step-by-step explanation:
Area of rectangular barn = 200 (sqft)
Length= Width + 10
Length x Width = 200 ==> (Width+10)Width = 200
Width² +10Width -200 = 0===> width = 10 ===> length = 20
Answer:
Johnny is wrong.

Step-by-step explanation:
Johnny is wrong.
A better definition would be:
is the set of all elements that belong to at least one A or B.
So, the elements that belong to both A and B, like c and d in this exercise, also belong to
.
So:

Answer: 64 ................ :)
Step-by-step explanation: