CHAPTER 9
SECTION 9.1
Modeling Linear Systems
MINI LESSON
Modeling Linear Systems
A system of equations can be used to model situations where two quantities are related in different ways.
Each equation represents a relationship between variables.
Solving the system finds the values that satisfy both equations at the same time.
Question 1
Alex had $1.70 in nickels and dimes on his desk. There were 25 coins in all.
If n represents the number of nickels and d represents the number of dimes, which system of equations models the situation?
Question 2
Courtney went to a coffee shop to purchase lattes and donuts for her friends.
One day she spent $15.50 on four lattes and two donuts. The next day she spent $18.10 on three lattes and five donuts.
If x represents the cost of one latte and y represents the cost of one donut, which system correctly models the situation?
Answer Key
Modeling Linear Systems
- 1.B. n + d = 25 and 0.05n + 0.10d = 1.70
- 2.C. 4x + 2y = 15.50 and 3x + 5y = 18.10