Sally has a discount card that reduces the price of her grocery bill in a certain grocery store by 5%. if c represents the cost of sally's groceries, write and expression to represent sally's grocery bill.

State if the two triangles are congruent. if they are, state how you know?

Write a function for a rotation 90 degrees counter clockwise about the origin, point 0

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) = .