In ΔDEF, DE = 11, EF = 9, and angle E = 140°.

Which equation correctly uses the law of cosines to solve for the third side?

Mrs. morton has a special reward system for her class. when all her students behave well, she rewards them by putting 3 marbles into a marble jar. when the jar has 100 or more marbles, the students have a party. right now, the the jar has 24 marbles. how could mrs. morton reward the class in order for the students to have a party?

Does anyone know how to do geometryme with this problem

Given: pqrs is a parallelogram prove: pr and qs bisect each other at t