Answer:
39
Step-by-step explanation:
-3x(-13) = 39.
If this question was asking for something different I apologize.
To calculate the square root, you can either use the √symbol on a calculator or you can manually find it using Prime Factorization. For non-perfect squares, Prime Factorization is the way to go.
The first two steps work for solving large perfect squares as well.
1. Divide your number into perfect square factors.
2. Take the square roots of your perfect square factors.
3. If your number doesn't factor perfectly, reduce your answer to simplest terms.
4. If needed, estimate. In some cases if you have memorized some of the square roots, you can estimate where the number would be.
ie.

you know that

and

, so you can estimate that the

would be between 7 and 8 but closer to 8.
5. <span>Alternatively, reduce your number to its lowest common factors as your first step.</span><span> Finding perfect square factors isn't necessary if you can easily determine a number's prime factors (factors that are also prime numbers).
ie. </span>

=

=

=

Hope this helped!!!
Answer:
The interest rate is 7.58%
Step-by-step explanation:
Compound continuous interest can be calculated using the formula:
A = P
, where
- A is the future value of the investment, including interest
- P is the principal investment amount (the initial amount)
- r is the interest rate in decimal
- t is the time the money is invested for
∵ Angus has $3,000 he want to invest
∴ P = 3000
∵ The interest rate is compounded continuously
∵ Angus has $5,500 in 8 years
∴ A = 5500
∴ t = 8
→ Substitute them in the rule above to find r
∵ 5500 = 3000
→ Divide both sides by 3000
∴
= 
→ Insert ㏑ in both sides
∵ ㏑(
) = ㏑(
)
→ Remember ㏑(
) = n
∴ ㏑(
) = 8r
→ Divide both sides by 8
∴ 0.07576697545 = r
→ Multiply it by 100% to change it to a percentage
∴ r = 0.07576697545 × 100%
∴ r = 7.576697545 %
→ Round it to the nearest hundredth
∴ r ≅ 7.58
∴ The interest rate is 7.58%