Use formulas to solve problems by substituting numbers or expressions for the variables. This can entail rearranging the formula so that the required variable is on one side of the equation.

There are many formulas used in math, including those for area, surface area, work, distance, perimeter and compound interest, but the same basic steps are required to solve them.

**Identify the necessary formula****Solve the problem using the formula****Check the answer and give an explanation**

Read the problem to understand what it is asking and what the known variables are. Identify the correct formula to use and plan out a strategy to solve for the specified variable.

Use the formula and solve in terms of the known variable. Do this by rearranging the known variables in the formula, performing operations so that the specified variable is the only variable left on one side of the equation and substituting the known variables into the formula to find the answer.

Substitute all the values for the variables into the original formula to make sure the answer is correct. Check also that all measurements are in the correct units, especially when the problem involves solving for perimeter, area or volume. For some questions, it may also be necessary to explain the strategies used to solve the problem.