Write the equation of circle with diameter of 10 units centered at (- 2, 1) .

Step-by-step explanation:

We want to write the equation of a circle with a diameter of 10 units centered on (-2, 1).

Recall that the equation of a circle has the standard form:

Where (h, k) is the center and r is the radius.

Since our diameter is 10, our radius is 5.

And since the center is at (-2, 1), h = -2 and k = 1.

Substitute:

And simplify. Hence, our equation is:

the arc length is found by finding the circumference of the full circle (2xpixradius) and then dividing by 4 to find just one quarter of the circle (90 degrees).