Leila bought 4 CDs that were each the same price. Including sales tax, she paid a total of 58.80. Each CD had a tax of 0.90. What was the price of each CD before tax?

$13.80, got this answer by taking 0.90 and dividing 4 by it. The subtracted that answer from 58.80. Once i found that solution i divided it by 4 and got 13.8

answer: option a.

step-by-step explanation:

you know that the quadrilateral opqr ( a four sided figure) is inscribed in circle. this means that all its vertices are on the circle.

then, by definition, the opposite angles of the quadrilateral are supplementary, this means that the sum of their measures is 180 degrees.

you can observe in the figure that the angles ∠opq   and the angle ∠orq   are opposite, therefore:

then, can be used to d to calculate the measure of ∠opq