Initial ideas
EQ~ How do variables help us generalize patterns and behaviors? 11/20/25
Do Now~ Stories & Variables Describe each of these stories mathematically. This means writing an algebraic expression for each story.
I’m counting the days until my birthday! Actually, there are w weeks and d days until the day arrives. Write an expression indicating the total number of days I must wait.
My dog is dieting. He weighed p pounds at the beginning of August and lost m pounds during the month. In September, he gained 2 more pounds than the amount he lost in August. Write an expression to show how much he weighs now.
Gina bought f muffins at c cents each. Write an expression to show how much she paid.
My older brother makes $a a day and spends $b a day. Write an expression to show how many dollars he’ll save in 10 days.
When I counted the change in my pocket, there were q quarters and d dimes. Write an expression that tells how many cents I have.
Activity 2~Evaluating Algebraic Expressions
The school day ends in h hours and m minutes.
Write an algebraic expression that tells how many minutes until the end of school.
In this expression, replace h with 2 and m with 17. Find the value of this numerical expression. Explain the meaning of the answer.
When my sister started using my phone, its battery was 100%. Yesterday, she used it for 1 hour and 4 minutes, and today, she used it for 2 hours and 2 minutes. My cell phone now has 25% battery left, how much time would I have if my phone were at 100%?
Once you have answered the first question can you now write an expression using h for hours
and m for minutes that can tell us how much time is left on your prone at any moment?
This activity is intended to:
~ to teach students what combining like terms means, and the operations involved.
~ leads students to develop a solid understanding of how to represent a problem with variables
~ leads students to develop a clear knowledge of algebraic operations using variables
~ allows students to see an aspect of the short cuts algebra offers over arithmetic
We have the following scenario:
There are 4 groups of people at Nicks’ Pizza shop having lunch, and the waitress has to take their orders fast.
If you were the owner of the pizza shop,what method(s) would you use to take orders really fast so that the customers don;’t get upset and walk out due to waiting too long?
Use the group assigned to you to develop a fast way to take the order:
Group 1~The Dominguez Family
Juan: slice of sausage, slice of sausage, garlic knots, large drink
Maria: slice of cheese, medium drink
Jose: slice of cheese, slice of cheese, medium drink
Simone: slice of cheese, slice of pepperoni, medium drink
Julio: slice of pepperoni, slice of pepperoni, medium drink
__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Group 2 ~ Friends out for pizza
Matthew: slice of sausage, slice of cheese, large drink
Sarah: slice of pepperoni, medium drink
Elizabeth: slices of cheese, slice of cheese, medium drink
Jonathan: slice of meat special, slice of cheese, large drink
Peter: slice of cheese, slice of pepperoni, medium drink
Abby: slice of cheese, medium drink
____________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Group 3 ~ Friends out for pizza
Kenny: slice of pepperoni, slice of cheese, large drink
Keisha: slice of pepperoni, medium drink
Malaki: slice of sausage, slice of sausage, medium drink
Kayla: slice of cheese, slice of cheese, small drink
Brandon: slice of sausage, slice of pepperoni, small drink
Jeremy: slice of cheese, large drink
____________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Group 4 ~ The Miller Family
Reggie: slice of sausage, slice of sausage, medium drink
Sabrina: slice of pepperoni, medium drink
Samuel: slice of cheese, slice of pepperoni, medium drink
Johanna: slice of sausage, slice of cheese, medium drink
Michelle: slice of cheese, medium drink
______________________________________________________________________________________________________________________________________________________________________________________________
Questions to consider:
a) How would you place this order so it would be the simplest for the server?
b) Why did you choose to order it the way you did?
c) What operations did you perform and why?
d) How do you know your method is correct and works?
e) How would you represent this algebraically?
f) What would be the next step?
g) Why did you combine some items and not all the items?
Use substitution of the given values to evaluate the following algebraic expressions.
H) Find the value of 3x – 2x for x = 2 I) Find the value of 3x – 2y for x = -3 and y = -4.
J) Evaluate d/6 + 28 for d = 39; K) Evaluate 3(p – 7) for p = 4.
L) Evaluate − 3a − 2b +c when a = 2, b = 4, c = -4
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