Question

Find an equation of a line tangent to a circle x^2+y^2=10x^2+y^2=10 at (3,1).
A) y=1/3x
B) y = -3x + 10
C) y=1/3x+10/3
D) y = -3x + 1

Answer 1

Is this the equation of circle
\[x^2+y^2=10x^2+y^2=10\]
?

Answer 2

Equation of circle is x^2 + y^2 = 10. So, the center is (0,0). Now, you have to find the equation of the line passing between (0,0) and (3,1). Then, find a line perpendicular to this line passing through (3,1).

Answer 3

yes

Answer 4

Those are the steps. Tangent = Line perpendicular to the line connecting to the center.

Answer 5

I dont know any of this. im home schooled lol

Answer 6

my parents are highschool drop outs, im on my own

Answer 7

You just need to take it one step at a time and breakdown this problem into three problems:

1) Find center of circle. Easy part given the equation it is (0,0).
2) Find equation of a line passing through two points (you should be able to find the procedure anywhere online)
3) Find equation of line perpendicular to the line in step #2 (again, steps and procedures available online)

Answer 8

I think its B. Is that right?

Answer 9

This diagram should help clarify the tangent and equations needed.

Answer 10

B is correct. But, again, more important how you get there.