# algebra

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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?

• algebra - ,

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.

• algebra - ,

Thanks!