# Building Functions from tables, graphs & context (1)

```Bellringer
TBD based on QUIZ RESULTS!!!!
Coordinate Algebra
UNIT QUESTION: How can we use real-world
situations to construct and compare linear and
exponential models and solve problems?
Standards: MCC9-12.A.REI.10, 11, F.IF.1-7, 9, F.BF.1-3, F.LE.1-3, 5
Today’s Question(s): 1. How can an unknown
quantity be represented in an expression or an
equation? What is the difference between the
slope and shape of a linear function and an
exponential function?
Standard: MCC9–12.F.BF.1, F.LE.2
For each problem, write an equation to
represent the situation and then answer
the question.
Example 1:
Willem buys 4 mangoes each week,
and mango prices vary from week to
week. Write an equation that
represents the cost of the mangoes. If
each mango costs \$1 this week, what
is the total cost of his mangoes for this
week?
Example 1
 Let the total cost of the mangoes = c.
 Let the price of each mango = p.
 The number of mangoes = 4.
 total cost = the number of mangoes • the price of each
mango
 c = 4p
 If the cost of mangoes = \$1, substitute 1 in for p.
 c = 4p
 c = 4(1)
 c=4
 The total cost for Willem to buy mangoes this week is \$4.
For each problem, write an equation
to represent the situation and then
Example 2:
Kerin drives at a speed of 55
miles per hour on the highway
for her job. Write an equation
that represents the distance she
travels. If one day she drives for
6 hours, how many miles did she
travel?
Example 2
 Let distance = d.
 Let time = t.
 The rate = 55 mph.
 distance = rate • time
 d = 55t
 If the time = 6 hours, substitute 6 in for t.
 d = 55t
 d = 55(6)
 d = 330
 Kerin drove 330 miles that day.
Number 3
 Let the total number of students Mr. Stevens teaches = t.
 Let the number of students in each class = s.
 The number of classes = 4.
 t = 4s
 If Mr. Stevens has 30 students in each class and all of them
are present, substitute 30 in for s.
 t = 4s
 t = 4(30)
 t = 120
 Mr. Stevens taught 120 students on the day when all of his
students were present.
Number 4
 Let the number of hours Jessica has to read = h.
 Let the total number of pages = p.
 The number of pages per hour = 12.
 p = 12h
 If the number of hours = 3, substitute 3 in for h.
 p = 12h
 p = 12(3)
 p = 36
 Jessica read 36 pages of her novel.
Ok enough of that….
What are some other
ways we can be
presented functions?
Graphs
Tables
Homework &amp; Summary
6 creating from context
4 creating from a graph
5 creating from a table
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