A bag of coins contains only quarters and dimes. • The number of dimes in the bag can be represented by x.
• The number of quarters is 6 more than twice the number of dimes.
• There are a total of 276 coins in the bag.
What is x, the number of dimes in the bag?

helpp pls

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)