1. f(x) = x – 8 g(x) = 7 – 2x h(x) = 𝑥 −9 5
Bellringer (5 minutes)
Given the following functions, solve the problems:
f(x) = x – 8 g(x) = 7 – 2x h(x) = 𝑥 −9 5
What is the value of f(2)?
What is the value of g(– 2)?
What is the value of h(44)?

2. Algebra 1
October 1 & 2, 2018

3. announcements
October 10: Last day to complete/turn in late work and quizzes
October 12: Last day of the Nine Weeks
For people who want to take retakes after school, you will have to wait for tomorrow (10/2)
I will be in math tutorials (Room 438)

4. announcements Mini-quiz: Friday/Monday Unit assessment
3 to 5 questions
We will review Wednesday/Thursday
Unit assessment
Window is October 4 – 12
We will take it as close to the 12th as we can

5. Homecoming week schedule
Monday/Tuesday: Review for unit assessment
Wednesday/Thursday: Unit assessment
Friday: Unit assessment (make-ups)
I will make other make-ups available for quizzes until Wednesday of homecoming week

6. f(x) = x – 8 g(x) = 7 – 2x h(x) = 𝑥 −9 5
Combining functions
Up until now, we’ve been doing functions on their own
But what happens if we string the functions together?
Let’s take the following functions:
f(x) = x – 8 g(x) = 7 – 2x h(x) = 𝑥 −9 5
Let’s say we want to figure out what the value of f(2) + g(5) is?

7. Combining functions First: Don’t have a panic attack.
The initial step has not changed  you still need to identify which function you will be using
In this case, the functions are:
f(x) = x – 8 g(x) = 7 – 2x
Now, I recommend finding the value of each smaller part:
f(2) = 2 – 8 = – 6
g(5) = 7 – 2(5) = 7 – 10 = – 3

8. f(x) = x – 8 g(x) = 7 – 2x h(x) = 𝑥 −9 5
Combining functions
Now we can combine the values for f(2) and g(5)
f(2) + g(5) = – 6 + (– 3) = –9
Questions?
So, back to these functions:
f(x) = x – 8 g(x) = 7 – 2x h(x) = 𝑥 −9 5
Here’s a new question: What happens when you set functions equal to each other?

9. f(x) = x – 8 g(x) = 7 – 2x h(x) = 𝑥 −9 5
Combining functions
First: Don’t have a panic attack.
Now, let’s go back to these functions:
f(x) = x – 8 g(x) = 7 – 2x h(x) = 𝑥 −9 5
For what value of x is f(x) = g(x)?
This is actually simple  you literally set the functions equal to each other
So you get: x – 8 = 7 – 2x
Remember how to solve equations?

10. Combining functions
Remember how to solve equations? That’s all you’re doing now!
x – 8 = 7 – 2x
x – 8+ 2x = 7 – 2x + 2x
3x – = 7 + 8
3x = 15
x = 5
Questions so far?