Question

find the equation of a line with a slope of -1 which is tangent to the circle x^2 + y^2 = 9
tell me how ya did it, and also, what does tangent mean again :D?

Answer 1

tangent means line that only touches the point to the curve

Answer 2

I knew that.

Answer 3

ok

Answer 4

:D

Answer 5

the 9 means the radius of the circle is 3???

Answer 6

y=-1x+b

Answer 7

but.. but what's Y...?

Answer 8

twitch

Answer 9

hold up

Answer 10

hahd :(?

Answer 11

wait sorry my mom was talking to me

Answer 12

im on it

Answer 13

<3 :D

Answer 14

ahgg i cant figure it out sorry, repost it and someone might be able to i think i can solve it but i have tennis lesson coming up so i have to go, once again sorry bye

Answer 15

seeya, and thanks.

Answer 16

The tangents form triangles with the with the x-axis with short sides 3 so hypotenuse is sqrt(18) giving plus or minus 3 sqrt 2

So lines are y = -x +- 3sqrt2

http://www.wolframalpha.com/input/?i=plot+x^2+%2B+y^2+%3D+9%2Cy%3D-x-3sqrt2%2Cy%3D-x%2B3sqrt2+%2Cx%3D0%2Cy%3D0%2Cy%3Dx%2C+x%3D-5..5%2Cy%3D-5..5

Answer 17

lol yh thts what it worked out to be but i thought since its hs math its prob integer so i was screwing up on calc