What is the probability that in a class of 20 students, 2 of them will have the same birthday?

Ten members of balin's soccer team ran warm ups for practice. each member ran the same distance. their combined distance was 5/6 of a mile. to find the distance that each member ran, balin wrote the expression below.

In the diagram below,abc is congruent to dec what is the value of x

Find the length of the normal and the angle it makes with the positive x-axis. (see pictured below)