A set has closure under an operation if performance of that operation on members of the set always produces a member of the same set; in this case we also say that the set is closed under the operation.
A closure property is a certain rule that holds <u>if it is true for all elements of a set under the given operation</u> and a closure property does not hold <u>if there is at least one pair of elements that do not follow the closure property under the given operation.</u>
Therefore, Emma is correct, because you can find a counterexample (7:2=3.5) that gives you a non-integer answer.
Answer: correct option is B
-3(2x-4)+8x-8
-6x+12+8x-8
2x+4
x=2
Split the shape in 3 rectangles
4x2=8x2= 16 ( the bottom and top rectangle)
6x2= 12 (middle rectangle)
16+12=28
Sorry I'm in high school.. but according to my physics class, the instantaneous speed is when t (time) is 0, or whatever you'd use (like x).. anyways, when t=0, the instantaneous speed would be 3 ft/s, and the instantaneous acceleration is 0.