Answer:
The area of this figure is 45 square units.
The question is a bit ambiguous: you may mean

or

Anyway, in both cases, the domain of a function involving a square root is found by imposing the content of the root to be greateer than or equal to zero. So, in the first case you have

In the second case, you have

Factor trees help you find the prime factorization of a number by breaking down the number by what two numbers equal the number you are trying to find the prime factorization of.
Answer: 5,600
Explanation: By multiplying 0.10 (4,000) to find the interest for one year, you get 400. Because she is using this loan for 4 years you multiply that one year interest by 4. 400 times 4 is 1600. Then, you add that 1600 (which is the total interest for 4 years) to the loan, to get an answer of 5,600.