My father taught me a method that I call, 'throwing some thing over the wall'. There is a sample equation for the first picture that shows you how it works. It's a great way to help isolate the variable and I hope that it works for you. The second picture contains the answers I got through the use of this method. I'm sorry for the messy handwriting; I was on a bus.
Answer:
Step-by-step explanation:
Answer:
Center: (4,8)
Radius: 2.5
Equation: 
Step-by-step explanation:
It was given that; the endpoints of the longest chord on a circle are (4, 5.5) and (4, 10.5).
Note that the longest chord is the diameter;
The midpoint of the ends of the diameter gives us the center;
Use the midpoint formula;

The center is at; 
To find the radius, use the distance formula to find the distance from the center to one of the endpoints.
The distance formula is;




The equation of the circle in standard form is given by;

We substitute the center and the radius into the formula to get;


Answer: 4
Step-by-step explanation: 2 + 2 = 4
Answer: C
Step-by-step explanation:
If we know the value of the car decreases $500 for every 1,000 miles, and that the car is driven about 10,000 miles every year, that means that you need to take the total value of the car (23,000) and subtract it from the amount of money it is losing per year. Again, the car is driven about 10,000 miles per year, so that means that the car will most likely continue to be driven 10,000 miles per year. If you do the math, for one year, the value of the car will drop $5,000 ($500 x 10, because it is $500 per every 1,000 miles) So, for each year, you can just multiply the number of years by $5,000 to find out how much the vehicle has depreciated over time.
Hope this helped you and made sense! Feel free to ask me any questions you have!