If mac lipstick lasts 2 weeks, and i've used 76% of it, how long do i have left until it runs out?

How can constraints be used to model a real-world situation?

Parabolas y=−2x^2 and y=2x^2+k intersect at points a and b that are in the third and the fourth quadrants respectively. find k if length of the segment ab is 5.

The cost of a taxi ride includes an initial charge of $2.00. if a 5km ride cost $6.00 and a 10km ride cost $10.00, determine the cost of a 15km ride.