If 12 keychains cost $9 then how much does 20 keychains cost? $_ Also if you could may you provide steps on how you got the answer

Lena reflected this figure across the x-axis. she writes the vertices of the image as a'(−2, 8), b'(−5, 6), c'(−8, 8), d'(−4, 2).

Describe a situation that you could represent with the inequality x< 17

The length of an intercepted arc of a central angle of a circle is 4 cm. if the radius of the circle is 5 cm what is the measurement of the central angle to the nearest whole degree