Consider the circle of radius 5 whose center is (0,0). Write the equation of the line tangent to the circle at (3,4).

Question

anonymous · Answer

$$x^2+y^2=r^2$$where r is the radius.

anonymous · Answer

What will be the equation of the circle with a radius 5?

amistre64 · Answer

the slope of a tangent to a circle is the perp slope of the line from the center

anonymous · Answer

X^2 + y^2=10?

amistre64 · Answer

slope from center to point is:$$\frac{y_1-y_0}{x_1-x_0}$$perp slope is just flip and negate$$-\frac{x_1-x_0}{y_1-y_0}$$

anonymous · Answer

|dw:1344354134986:dw|,

amistre64 · Answer

Ryan is answering a confused reading of your question ....

anonymous · Answer

Well is my method still wrong then?

anonymous · Answer

So the slope would be -3/4

anonymous · Answer

Isolating y and then finding the derivative and then plugging the given point and you find the slope. Then use point slope form with the slope you found and the given point

anonymous · Answer

Hi,
suppose you have a circle
$$ x^2 + y^2 = r^2 $$
then the tangent line to this circle is given as:
$$ xx_1 + yy_1 = r^2 $$
at any point (x1,y1) on the circle
Now substitute x1 = 3 and y1 = 4:
$$ 3x + 4y = 5^2 $$
$$ 3x + 4y = 25 $$

amistre64 · Answer

if your employing calculus, then no

amistre64 · Answer

slope of the tangent line is:  -3/4  yes

anonymous · Answer

My method is tedious but I still have to use a derivative so is it still wrong?

amistre64 · Answer

Ryan, your method reads fine now that i know the method your thinking of :)

anonymous · Answer

Thanks every body I think I got now! :)

amistre64 · Answer

something seems wrong with the posting mechanism; anyone else getting multiple posts of the same thing?

anonymous · Answer

Brohoofs for everyone "brohoof" good job guys!