posted by Shan on .
1.)Find the equation of the circle with center (1, 3) and radius r =2.
2.)Find the area of the circle of the above problem?
2) I'll start with this part of the problem first. You know the radius of the circle is 2.
And the area of a circle is pi*(radius^2)
So pi*(2^2) = 4*pi...
1) So first get a piece of paper and pencil. I'll wait.
Ok. Now that you have a paper and pencil draw the x-y coordinate plane (2 perpendicular lines, the horizontal is the x, the vertical is the y). Mark off 5 tick marks on each line. This will be good practice.
Using this coordinate plane, and knowing that the x and y values of the center of the circle are 1 and 3 respectively, plot this point. Then plot the points that are 2 to the left of the center, 2 to the right, 2 below the center, and 2 above.
Connect the 4 points around the circle, and you've drawn the circle.
The equation of a circle is as follows:
(x-h)^2 + (y-k)^2 = radius^2. where the center is (h, k).
If h is 1, k is 3, and radius = 2.... I think you can take it from here. Hope this helped. Peace out.