NEEED HELP! please someone help!!

Question

A small radio transmitter broadcasts in a 21 mile radius. If you drive along a straight line from a city 26 miles north of the transmitter to a second city 29 miles east of the transmitter, during how much of the drive will you pick up a signal from the transmitter?

____ miles  

Answer 1

Draw a figure.

This question really wants to know the length of a chord of a circle.

The circle is x² + y²= 441

The chord is given by y=(-27/29)(x-29)

Solve those 2 equations simultaneously and then use the distance formula to find the length of the chord.

BTGW: if you use DESMOS to draw your figure, DESMOS will give you the co-ordinates of the intersection (no algebra!) and then the distance formula is straight forward.