1. ## cartesian plane

find the radius of a circle with center at (-2, 1), if a chord length of 10 is bisected at (-3, 0).

can you help me with this one? i think ill know how to solve it if i know the drawing.

by the way, answer is 33 or 5.196 according to our prof.

2. Originally Posted by proview
find the radius of a circle with center at (-2, 1), if a chord length of 10 is bisected at (-3, 0).

can you help me with this one? i think ill know how to solve it if i know the drawing.

by the way, answer is 33 or 5.196 according to our prof.
yes, that's the answer. i wish i had my graphing software and stuff on this PC so that i could show you the diagram.

anyway, plot the center, and draw a line connecting it to (-3,0). the chord is perpendicular to this line. so draw that (the line you drew first is the perpendicular bisector of the chord). then use the formula $\text{chord length} = 2 \sqrt{r^2 - d^2}$, with $r$ and $d$ as shown here. you can figure out the value of d using Pythagoras' theorem, and then just solve the equation for r

3. thanks for help. i got the drawing and realized that you can use Pythagorean theorem to solve it all the way.