Answer:
The amount of interest earned at the end of 14 years would be $672.3486
Step-by-step explanation:
This is a simple interest problem.
The simple interest formula is given by:

In which E are the earnings, P is the principal(the initial amount of money), I is the interest rate(yearly, as a decimal) and t is the time.
In this problem, we have that:

So

The amount of interest earned at the end of 14 years would be $672.3486
A = bh/2
2a = bh
2a/b = h
h = 2a/b
Hi there!

First we need to work out the parenthesis, which can for instance be done using rainbow technique.

Now subtract 3 from both sides.

And finally add 3x to both sides.

The 4th answer choice is correct.
1st and 2nd pictures are for finding area and 3rd picture is for finding perimeter
hope you understood well and if not and you can ask again