The length of a side of a square is given by the expression 3x - 1 and its perimeter is 20 cm. Write and solve an equation to find the value of x. Which of the following
have both the correct equation and side length of the square?
A. 4(3x - 1) = 20; side length = 4.25 cm
B. (4 x 3x) - (4 x 1) = 20; side length = 5 cm
C. 12x - 1 = 20; side length = 1.75 cm
D. 4(3x - 1) = 20; side length = 2 cm

We have been given that a person places $6340 in an investment account earning an annual rate of 8.4%, compounded continuously. We are asked to find amount of money in the account after 2 years.

We will use continuous compounding formula to solve our given problem as:

, where

A = Final amount after t years,

P = Principal initially invested,

e = base of a natural logarithm,

r = Rate of interest in decimal form.  

Upon substituting our given values in above formula, we will get:

Upon rounding to nearest cent, we will get:

Therefore, an amount of $7499.82 will be in account after 2 years.