19. solve for r: c=2pi r
a) r=c/2pi
b) r=2cpi
c) r=2pi/c
d) r=1/2cpi

angle q= 92 degree

step-by-step explanation:

the solution is in the picture

when a quadrilateral is inscribed in a circle, the opposite angles are supplement to each other. in other words, the sum of the 2 angle is 180 degree

for ex: the reciprocal of 3/4 is 4/3. it is the opposite.

reciprocal definition:

a mathematical expression or function so related to another that their product is one; the quantity obtained by dividing the number one by a given quantity.