**CCSS.Math.Content.8.EE.C.7: **Solve linear equations in one
variable.

**CCSS.Math.Content.8.EE.C.8** Analyze and solve pairs of
simultaneous linear equations.

**CCSS.Math.Content.8.F.A.1** Understand that a function is a rule
that assigns to each input exactly one output. The graph of a function is the
set of ordered pairs consisting of an input and the corresponding output.

**CCSS.Math.Content.8.F.B.4** Construct a function to model a
linear relationship between two quantities. Determine the rate of change
and initial value of the function from a description of a relationship or from
two (*x, y*) values, including reading these from a table or from a graph.
Interpret the rate of change and initial value of a linear function in terms of
the situation it models, and in terms of its graph or a table of values.