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)?

Algebra 1 October 1 & 2, 2018

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)

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

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

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?

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

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?

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?

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 – 8 + 8 = 7 + 8 3x = 15 x = 5 Questions so far?