Simplify the expression

−6 − 6f + 7 − 3f − 9.
please help me its for homework due today! :)

Janie has $3. she earns $1.20 for each chore she does and can do fractions of chores. she wants to earn enough money to buy a cd for $13.50. write an inequality to determine the number of chores, c, janie could do to have enough money to buy the cd.

Which one ? is the answer and how to find this answer

Evaluate cos2θ for cosθ = square root of 3/2