The question is worded a bit strangely (in my opinion anyway), but I think your teacher wants you to describe how exponents work.
Let's say we had the expression 
The base is 5 as its the bottom most value (think of something like the base of a tree or building). The exponent is 3.
The exponent of 3 tells the reader to multiply the base 5 by itself 3 times like so

With larger exponents, it becomes more tedious to write out all the repeated multiplications, which is why many calculators have an exponent button to save time.
Answer:
6π cm
Step-by-step explanation:
Answer:
if we are simplifying, the answer is 6x⁴y²
Answer:
Let y(x)="x is valid and x has true premises" and z(x)="x has a true conclusion".
Step-by-step explanation:
The universe U is the collection of all arguments so that x∈U. The statement uses the universal quantifier ∀ represented by the word "Every". The words "valid", "with true premises" and "has a true conclusions" are properties of an argument x.
We can interptet the statement as: "For all x, (x is valid and x has true premises)→(x has a true conclusion)". Symbolically, (∀x)(y(x)→z(x)). The implication → can be read as "if y(x) then z(x)".
Answer: x=-10, y=13
Step-by-step explanation:

+2y-2y = 0, eliminating y is much easier. So -3x-5x = -8x and 56+24 = 80

Substitute x in any equations but only 1 equation (Don't substitute in both equations.)
For me, I'd substitute x in -3x+2y=50

So the answer is x = -10, y = 13