How do you prove the identities?

1) 1- cos²θ ≡ sin²θ
2) (1-sin²θ) tanθ≡ cosθ sinθ

Acircular city park has a sidewalk directly through the middle that is 111 - feet long. if each bag of fertilizer covers 50 square feet, then determine how many bags of fertilizers the parks and recreation department needs to use to cover the circular park. ignore all the sidewalks around and through the park.

45% of the trees in a park are apple trees. there are 27 apple trees in the park. how many trees are in the park in all?

Write a description of each inequality. 1. -5a + 3 > 1 2. 27 - 2b < -6 (this < has a _ under it) 3. 1/2 (c + 1) > 5 (this > has a _ under it)