6. Find the value of k if: (a) the line 2x – y +k=0 is a tangent to the circle x2 + y2 = 5.
​

On this site you will find the complete answer

Step-by-step explanation:

https://www.quora.com/How-can-one-find-the-values-of-k-for-which-the-line-2x-k-is-tangent-to-the-circle-with-the-equation-x-2-+-y-2-5

-3

step-by-step explanation:

a drawing really does here:

so i draw the horizontal line y=2 and the vertical line x=-2 at this intersection i put b (this is where my right angle is going to be).   so point b is at (-2,2).   point a is 5 units long and is also on y=2 so this point has to be (3,2) or (-7,2) -doesn't matter i will go with (3,2).

now we know c is at (-2,y) we don't know the y yet bet we know that c is on x=-2.

we have the area of the triangle is .5bh=12.5

we know the base length is 5 (ab)

we have the height is (2-y) if you look at your

plug in

.5(5)(2-y)=12.5

solve for y to get the y-coordinate for c

2.5(2-y)=12.5

divide both sides by 2.5 giving:

2-y=5

now subtract 2 on both sides

-y=3

y=-3