Question

Which point lies outside the circle with equation (x - 2)^2 + (y + 3)^2 = 4?

Answer 1

@Ahmad1

Answer 2

pls help

Answer 3

where the choices are dude @cocopuffs90 ?

Answer 4

a) 2,4
b) 2,-4
c) 0,-3
d) 1,-4

Answer 5

@Ahmad1

Answer 6

okay in these types of questions , all you have to do is just substititute the points instead of (x,y) if the equation is not satisfied then that's the answer..
try and tell me what you see!

Answer 7

is it b?

Answer 8

@Ahmad1

Answer 9

@ybarrap do you happen to know if its b?

Answer 10

Compute the distance for each or your points to the center of the circle (<2,-3>). If it's greater than 2, that's your answer.

Answer 11

im still confused... so its not b right? @ybarrap

Answer 12

I think you are right dude @cocopuffs90

Answer 13

I just computed the distances, took me less than a minute and the answer just pops out. Do you know the distance between points? It's not b.

Answer 14

thanks man @Ahmad1

Answer 15

oh im wrong... and lost. i dont know the distance @ybarrap

Answer 16

oooooooooooooooops I am so sorry @cocopuffs90

Answer 17

@Ahmad1 Its all good dude

Answer 18

I did not read the question properly , what a shame!

Answer 19

haha its okay. so im guessing its (2,0) then right?

Answer 20

$$\sqrt{(y_2 - y_1)^2+(x_2 - x_1)^2}$$

Answer 21

even though it's right dude @cocopuffs90 the idea of the question is that the distance between the center and the point must be bigger than the radius , I also think tha's what our friend @ybarrap is saying

Answer 22

the center is the point (2,-3)

Answer 23

For example, for your first point, the distance is \(|<2,-3> - <2,4>|=\sqrt{0^2+(-7)^2}=7\) All the others are just as easy.

Answer 24

but (2,-3) isnt an option..

Answer 25

That's the center of the circle. This formula determines the distance from this center to each point in your options.

Answer 26

oooooohh so what exactly do i do now

Answer 27

I know but the distgance is measured between (2,-3) and the other points
that distance must be bigger than the radius which is 2

Answer 28

im not sure i know how to do that.. the formula

Answer 29

You need to find the distance for the next point, from <2,-4> to the center.