What is the process of changing from one form to another

Gabriel determined that his total cost would be represented by 2.5x + 2y – 2. his sister states that the expression should be x + x + 0.5x + y + y – 2. who is correct? explain.

If 3 3/4 lb. of candy costs 20.25 how much would 1lb. of candy cost

Solve the compound inequality. graph your solution. 2x – 2 < –12 or 2x + 3 > 7 x < –5 or x > 5 x < –5 or x > 2 x < –12 or x > 2 x < –7 or x > 5