1: name 3 methods for solving equations.
2: if a system has no solution, how does it look on a graph?
3: describe the characteristics of a graph when systems of equations have infinitely many solutions.
4: identify the solution to a system of equations for a graph.

1- The Substitution Method, Addition Method and Graphing method

2- The system is graphed as parallel lines, no interception between equations

3- One of the graphed lines is merged inside the other, it appears that an equation is missing.

4- The equations are graphed showing a common interception.

the revenue of the fitness center, y, is the product of two factors: the number of members and the fee paid by each member. there are 320 members now, but number of members goes down by 10 for each $5 increase in fees, so if x is the number of $5 price increases then members is equal to (320 - 10x). since the fee is currently $45, and the fee increases by $5 for every price bump x, the fee is given by (45 + 5x). so, revenue y is given by y = (320 - 10x)(45 + 5x).