Two angles have a common vertex but no common side. how can you tell whether the angles are vertical angles?

Answer these questions showing your work plz

14. (05.02 lc) what is the value of y in the solution to the following system of equations? (5 points) 2x + y = −4 5x + 3y = −6

Prove (a) cosh2(x) − sinh2(x) = 1 and (b) 1 − tanh 2(x) = sech 2(x). solution (a) cosh2(x) − sinh2(x) = ex + e−x 2 2 − 2 = e2x + 2 + e−2x 4 − = 4 = . (b) we start with the identity proved in part (a): cosh2(x) − sinh2(x) = 1. if we divide both sides by cosh2(x), we get 1 − sinh2(x) cosh2(x) = 1 or 1 − tanh 2(x) = .