Question

Radius OA of circle O has a slope of 2.5. What is the slope of the line tangent to circle O at point A?
0.8
2.5
-0.4
-5

Answer 1

|dw:14351729953:dw

Answer 2

\[\frac{HA}{oH}=2.5\]
is this ? what you mean ?

Answer 3

um i guess...it's cause the problem doesn't include a picture

Answer 4

you can draw an image (it help you to better understanding)

slope (oA) , slope(tangent line) =-1
because they are perpendicular

Answer 5

now you must guess the answer !
can't you ?

Answer 6

i dont know! i honestly dont know /:

Answer 7

if two line are perpendicular ...with slope \[m_1 ,m_2\]
so relation between them is :
\[m_1.m_2=-1\\m_1=2.5\\so\\m_2=?\]

Answer 8

m2 =?

Answer 9

-3.5? idk!

Answer 10

\[2.5 *m_2=-1\\m_2=\frac{-1}{2.5}=\frac{-1}{\frac{5}{2}}\\=\frac{-2}{5}\]

Answer 11

-0.4

Answer 12

bravo

Answer 13

yaaay! thank you!

Answer 14

understand ?

Answer 15

yes (:

Answer 16

it is not better to change your Id to igetmath ?

Answer 17

you dont like my id name? lol

Answer 18

i live mathematics