Given segment de is parallel to segment bc, what postulate or theorem can be used to prove the triangles are similar

Will used 20 colored tiles to make a design in art class. 5/20 of his tiles were red. what is an equivalent fraction for the red tiles?

Express in the simplest form: (x^2+9x+14/x^2-49) / (3x+6/x^2+x-56)

Apolice office claims that the proportion of people wearing seat belts is less than 65%. to test this claim, a random sample of 200 drivers is taken and its determined that 126 people are wearing seat belts. the following is the setup for this hypothesis test: h0: p=0.65 ha: p< 0.65 find the p-value for this hypothesis test for a proportion and round your answer to 3 decimal places.