We’re going to do more on factoring trinomials
and solving them Are you ready class?! (students: YEAH!)
Yay Math? (students: Yay Math!) When I say “Math” you say “yay”! Math!
(students: Yay!) Math!
(students: Yay!) When I say “yay” you say “math”! Yay!
(students: Math!) Yay!
(students: Math!) In case anyone at home is wondering,
this is my student’s jacket So I don’t blend in with the back Now I’m a floating head Now I’m not, okay (student: You are scary!) Do I look okay? Yay Math! Alright, we’re disrupting another class, sshh Question already, love it (student: What is a trinomial?)
What is a trinomial, good Trinomial is a polynomial, which is an equation With three terms One, two, three
(student: And then a polynomial is…) Is a many term equation (student: So a trinomial is a type of polynomial?)
A trinomial is a type of polynomial, excellent And we just heard someone said “I’m taking notes”,
That’s fantastic (student: That was me)
That’s great, I’m happy you said that So, first things first,
is there a greatest common factor? (student: Ah… no)
No There is no greatest common factor,
So we can start our factoring process If we were to do the ‘FOILing’ process;
what times what is 7x²? So what times what is 7x²? (student: Could it be 7x and then x?)
7x and x, is that clear? So we’re starting with that one,
now we’re going to go to this one What times what is 4? What do you think?
(student: 2*2 or 4*1) What do you want to start with?
(student: Let’s try 2 and 2) So let’s FOIL this, dude
(*caption note* First Outer Inner Last) I we were to FOIL to check,
forget about the signs for now Even though we can tell it will be both positive So, 7x², right? 7x*2 is?
(student: 14x) 2x, 4
Can these somehow add to make 29? (students: No)
No, so is it 2 and 2? (students: No) Let’s try 4 and 1, it’s like a game show Where do you want to put the 4? What do you think,
can you tell where you want to put the four? (student: In that one, the second one)
The second one Interesting that you should say that Could you put it in your own words
why it’s good to put the 4 here, and not here? (student: Because, umm… OH!)
OH! I love that moment! OH! (student: In the ‘O[uter],L[ast]’
you have to do 4*7x which would be 28x) (student: And then plus the 1x, oh) Exactly Where you going to say that, the ‘O’ sayer? Was that your intention? (student: Yeah, it was) Alright, so let’s make them plus, plus FOIL to check 7x², 28x [+] x, makes 29x, and 4. Yes? (student: The reason why you put
the 4 in the second parenthesis… …is because it’s bigger, and so it multiplies…)
With the 7 It will multiply with the 7 and that will make 28
and all we need is one more to make 29 (student: If you had put it in the first parenthesis then it wouldn’t be multiplied with the 7) Right, if you put the 4 here, 4 would be multiplied by x
and 1 would be multiplied by 7x so that would make 11x I’ll take the elevator Yeah, go ahead No, it depends on what the middle term is This elevator is broken So you put the bigger number wherever
you need to put the bigger number You’re still laughing, that’s awesome How many factors are still here? Two factors? So two factors, you set each to 0 to solve Because anything times 0, is 0 So we’re going to set the first factor which is
7x + 1 (student: Wait, I have a question)
Yes, yes, question? (student: That’s not the answer?)
No, the answer is solve for x, we have an ‘equals’ We need to solve for x This is factored, but we’re not done, solve! So, we set each factor to 0 x + 4=0,
I think everyone is writing, they don’t see that Everyone is writing, and when they look up, “oh” So now we solve, here we go! Minus 1 7x equals -1, divide by 7 *student sneezes*
Bless youuu! x=-1/7 *kids laugh* So high pitched I’m 1/16th mouse! In other words; great, great, great grandfather So these are the two answers.
Any questions? We solve both factors, set to 0 Alright, we’re going to do three more, you ready? Ready, Yay Math?
(students: Yay Math!) Please don’t do that Do you have the giggles? Do you really? (*student laughing*: I can’t breath)
That’s awesome Ladies and gentlemen, we have the giggles!