Ms. Sarah Gilpatrick is teaching her Algebra 1 part 2 students how to use Texas Instruments programmable calculators, called TI-Nspires, to solve systems of equations.
An equation system is two or more equations that share variables, such as x + 2y = 6 and 3x – y = 11. One way this system can be solved is by graphing each equation. The point where the two lines cross is the solution to the system.
In this example that would be when x = 4 and y = 1, or the point on the graph (4,1). Rather than creating their graphs by hand, Algebra students can enter each equation into the calculators. The TI-Nspire produces neat, clear graphs with the precise intersection point labeled.
Equation systems are used to find the value of two variables at the same time. For example, suppose Skyler and Emily buy food from the same pizza restaurant. Emily buys 2 slices and 2 iced teas for $12. Skyler buys 4 slices and 1 iced tea for $18. How much did each pizza slice (x) and each iced tea (y) cost?
[Hint: 2x + 2y = 12, and 4x + y = 18] Solution: (4,2)
