I am pretty sure it is talking about interest and $640 is what you start with, with a 3% interest for 2 years
To solve this problem you must apply the proccedure shown below:
1. You have that the ratio of the measures of the three angles is 
2. The sum of the interior angle of a triangle is 
3. Let's say that the measure of each angle is 
multiplied by the ratio. Therefore, you can write the following equation and solve for :
4. Therefore, the measure of each angle is:
The answer is: 
Note the general equation of a circle is x^2 + y^2 = r^2, with centre (0, 0) and radius: r.
So, our equation of a circle is (x + 3)^2 + (y - 1)^2 = 100
Subtract 100 from both sides and plug in the points. If it equals to 0, then the points satisfy the equation of the circle (ie lies on the circle)
In the process of laying out the question, you have given us important facts about the shaded area and the unshaded area. Now step back for just a second. If they're that deeply involved in the question, do you honestly expect that anybody can answer the question without seeing the picture of them ? ! ?
A vertical line i believe since x is constant
