Find the area of the pentagon

In triangle abc, the length of side ab is 12 cm, the length of side bc is 5 cm, and the length of side ca is 9 cm. find the measure of angle a using the law of cosines.

The length of a rectangle plus its width is 24 cm. the area is 143 square cm. what are the length and width of the rectangle?

Arental car company charges $45 plus 0.20 per mile to rent a car. mr. lawrence does not want to spend more than $100 for his rental car. write and solve an inequality to find how many miles he can drive and not spend more than $100. inequality: 45+0.20m is less than or equal to 100 solution: m is less than or equal to 275? interpret the solution: ?