? There is no graph included
A cross-section is the intersection of a solid and a plane.
Answer: Yes, the set of real numbers is closed under addition.
Explanation:
Let x and y be two real numbers. Their sum x+y is some other real number. This is what it means when we say the set of real numbers is closed under addition. Taking any two numbers and adding them will get us some other real number.
There is no way to have x+y be nonreal while x,y are both real.
time profit number
truck 10 min 1.00dollar t
car 12min 1.50 dollar c
boat 8min 0.60 dollar b
let the worker produce t trucks, c cars, and b boats.
10t+12c+8b=400
t+1.5c+0.6b is more than or equal to 35
t is more than or equal to 0
c is more than or equal to zero
b is more than or equal to zero
(this question is kinda wierd. i do not know if i am correct, because mine is not exactly a system of inequalities, but if you really need an answer, you can try this one.)
