This week your student will be learning to visualize, write, and solve equations. In previous grades, they did this work with numbers. In grade 6, they begin to use a letter called a variable to represent a number whose value is unknown.

Diagrams can help us make sense of how known and unknown quantities are related. Here is an example:

The three pieces in the diagram are labeled with the same variable, , so each piece represents the same number. We can write equations to represent the same relationship as shown in the diagram—for instance, and .

A solution to an equation is a number that is used in place of the variable and that makes the equation true. In the given example, the solution is 5. Substituting 5 for in each equation gives a true statement:  and