Question

Help please
A circle has its center at (-2, -3) and a radius of 3 units. What is the equation of the circle?
A.(x+2)^2+(y-3)^2=9
B.(x+2)^2+(y-3)^2=3
C.(x+2)^2+(y+3)^2=9
D.(x+2)^2+(y+3)^2=3

Answer 1

Use the equation of a circle. In this case it would be \[(x-h)^{2}+(y-k)^{2} = r^{2}\]

Answer 2

(-2-h)^2+(-3-k)=r? idk lol

Answer 3

im sorry i have trouble understanding math all the time :(

Answer 4

Okay. Let me explain. Give me a sec.

Answer 5

ok thankyou

Answer 6

So in the special case where the circle is off center, we can obtain the circle's equation through the Pythagorean theorem. The line in between (h,k) and (x,y) is the radius of the circle.

Answer 7

(h,k) is the centre of the circle. SO to solve your problem you just substitute for h, k and r

Answer 8

thankyou

Answer 9

Understand?

Answer 10

yes thankyou

Answer 11

Good.