Question

Can someone please explain how the answer is 143?

Answer 1

This is very meta.

Answer 2

h is 90 degrees, and we can trig the rest

Answer 3

How do we trig?

Answer 4

by some thrm, arc(HK) is twice angleG

Answer 5

we have a right triangle, and know leg lengths ....

Answer 6

trig to find \(\alpha\) and \(\beta \)

Answer 7

what trig function uses just the legs?

Answer 8

tan

Answer 9

so tanx = 12/4

Answer 10

then tan it

tan(a) = 12/4

inverse for the angle

Answer 11

Got it! Thanks very much!

Answer 12

yep

Answer 13

the required arc is therefore \(2\alpha\) :)