Given a regular decagon, what are the measures of the angles formed by (a) two consecutive radii and (b) a radius and a side of the polygon?
45°: 225°
60: 240°
122, 198
36, 72

dont understand

step-by-step explanation:

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4

9987

step-by-step explanation:

false

ok

hope this