Question

In the xy-plane, which of the following points lies inside the circular region of radius of radius 3 centered at (1,-2)
A (-1,1)
B (1,2)
C (0,-5)
D ( 3, 0)

Answer 1

you know that from your center the circle will extend AT MOST 3 units of magnitude in any direction
so you would compute the distance formula for each point from the center and make sure it is less than 3 units
the formula is for the point (a, b) (your center point) and any other point (x, y)
dist||(x, y), (a, b)|| = sqrt[(x- a)^2 + (y - b)^2]

Answer 2

ah the distance formula, thank you!

Answer 3

I think i got it now, thanks for the help!

Answer 4

:)