Johnny and Mark's combined age is 26 years old. Johnny is two years older than twice Mark's age. Write a system of equations and solve for each of their ages

Consider the diagram. which line segment has the same measure as st? rx tx sr xs

Solve with work adding cheese to a mcdonalds quarter pounder increases the fat content from 21g to 30g. what is the percent of change ?

The figures below are made out of circles, semicircles, quarter circles, and a square. find the area and the perimeter of each figure and give your answers as a completely simplified exact value in terms of π (no approximations).