Question

Find the radius of the circle whose equation is x² + y² = 4.

2
4
16

Answer 1

\(\LARGE x^2+y^2=r^2\)

Now, what is the radius of x² + y² = 4 ?

Answer 2

That is the standard equation of circle
now compare it :)

Answer 3

if \(r^2= Number\), then to figure out the radius alone, we take the square root of both sides
if \(\Large \sqrt{r^2}= \sqrt{Number}\)
if \(\Large r= \sqrt{Number}\)

Answer 4

16

Answer 5

No.

Answer 6

4 squared is 16.

Answer 7

it would be 16 if your equation was: x² + y² = 256
then the radius would be: \(\Large r=\sqrt{256}=16\)

Answer 8

bring the equation in a form where all the variables and constants are in the square form

Answer 9

I don't understand.

Answer 10

Is it 4 then?

Answer 11

\[x^2+y^2=(16)^2\]
considering @Zale101 example

Answer 12

when we compare the equation with \[\x^2+y^2=r^2\]
r=16

Answer 13

Here are some other example:
x² + y² = 256 radius is 16; because x² + y² = (16)^2
x² + y² = 81, radius is 9; becausex² + y² = 9^2
x² + y² = 64, radius is 8, because x² + y² = 8^2

Answer 14

ur equation : \[x^2+y^2=(?)^2\]

Answer 15

x² + y² = 4, the radius for this is..?

Answer 16

2

Answer 17

Bingo!

Answer 18

All the best!!! :)

Answer 19

Thanks!

Answer 20

x² + y² = 4, the radius is 2 because x² + y² = 2^2

Answer 21

Anytime

Answer 22

wow too long :)