Question

which is an equation of a circle with center (2,-1) that passes through the point (3,4)

Answer 1

do you recall the general equation for a circle?

Answer 2

what do you mean?

Answer 3

well, in order to construct the equation of a circle, its useful to remember the general equation of a circle from your material

Answer 4

it tends to be the distance formula of the 2 points, and then you generalize the center

Answer 5

im not exactly sure what you mean. that is all the question says..

Answer 6

the question does not exist in a vaccuum ... it is related to the material that you are spose to be studying

Answer 7

the material that you are spose to be studying would have presented you with the general equation of a circle; to which you would then be applying that general equation with the specifics stated in the problem

Answer 8

these are the options:
a) (x + 2)2 + (y - 1)2 = 26
b (x - 2)2 + (y + 1)2 = 13
c) (x + 2)2 + (y - 1)2 = 13
d) (x - 2)2 + (y + 1)2 = 26

Answer 9

those are good options :) .... one of them is the proper equation when the general setup is filled in ...

the general setup of a circle with radius (r) and center (h,k) is defined as:\[(x-h)^2+(y-k)^2=r^2\]

Answer 10

it doesnt give me the radius though. can you please help me out im still extremely confused....

Answer 11

the radius is the distance from the center to a given point; which can be formulated as:\[r^2=(x_o-x_1)^2+(y_o-y_1)^2\]

Answer 12

is it b?

Answer 13

close .. but no.

-2 and +1 are fine, but im getting 26 instead of 13

Answer 14

its d right :)

Answer 15

http://www.wolframalpha.com/input/?i=distance+%283%2C4%29+to+%282%2C-1%29

Answer 16

i like d yes :)

Answer 17

Thank you sooooooo much!

Answer 18

good luck ;)

Answer 19

thanks :)))