Video3: Multiply 2 Binomials EASY!!!
Algebra 1
Multiply 2 Binomials problem solving example
Another example that you will see when multiplying binomials is Z minus one times because permanent seeds means times four Z minus three. So we're going to write that on our papers. Z minus one, and I always put a line through my Z so I can tell the difference between a Z and bring this down a little. So I can tell the difference between a Z and a two. So Z minus one times. Four Z minus three.
So our very first step. Let me make the lighting a little bit better. That's all very first tip. Is that we're going to circle. Embarrass it. All right, we're going to circle. The. Sine N the middle. So we're going to circle the sign in the middle and the number. And. The back. Or the last number. Inside the parentheses. So that's our first step. We're going to look for the sun in the middle to circle, and the number behind it. Or the number and back over the last number, same thing. I'm a circle the negative one. I'm going to come over here. I'm going to look for the sign in the middle. I circle the number behind it. And back last number. Which is negative three.
So the second step. Is to write. The first number. Two times. So I'm going to write. I'll start here. All right, Z and Z, two times. Then, I'm going to write. The. Number that I circled. Two times. So I'm going to write negative one. Negative one. And then the last step. Is to all turn 8. B, numbers. From the other parentheses. We're going to alternate the numbers from the other parentheses. That means in this parentheses, we have a four Z and a negative three. Alternate means to take turns. So I'm going to put a four, Z here, a negative three here. I'm going to put a four Z here and a negative three here. And that's it. You put your multiplication symbols in between. And this is our foil, F O I L, which stands for first numbers outside numbers, inside numbers, and last numbers.
So if we look here inside this set of parentheses, the first number is Z, the first number in the second parentheses is a four Z if we look at the four numbers, it's like four desks sitting side by side. This is number one. That's number two. That's number three. And that's number four. Which two desk are on the outside. The Z that we wrote here, and the negative three that we wrote here. So if these are the two outside numbers, that means that these are the two inside numbers, the negative one, and the four Z don't forget your variables. And then L means last inside this set of parentheses, negative one is less. And this set of parentheses, the negative three is less. And then we're going to draw our peace signs. So we can make sure that we get our signs correct.
So I'll put a plus minus minus. Remember, we use a peace sign when we're multiplying or dividing. So we have a four in front of the Z, remember there's an imaginary one. So four times one is four. I see a Z here, and I see a Z here. So I see two Z's. I'm put a little two in the air that's your exponent to let you know how many Z's there are. I can put my imaginary one. So I have a circle my negatives I won't be confused. So I have a negative three and a positive one. So I'm going to shade in the negative for the negative three and the positive for the positive one. So that means that my answer is going to be negative. Let me circle it.
So that's going to be a negative three. And there's a Z one Z but don't forget your variable. Here, again, I have a negative one and a positive four. If you see nothing here, that means that there is an imaginary positive four. So I'm going to cancel out, scratch out my negative. For negative one and my positive for positive four, that means that my answer again is going to be negative four, four times one is four, and there's only one Z here, I see a negative one and a negative three. I'm going to scratch out my negative here and my negative here, which means that my answer is going to be a positive number. Three times one is three. And notice that there is no variables or no Z here. And all we're going to do is add the two metal numbers.
You always add, so I'm going to write the word. Add. This negative three means that I have to give you. So I have to give you $3. This negative four means that I have to give you $4. If I have to give you $3 and I have to give you $4, that means that I have to give you, so the negative sign means I have to give you a total of $7. And don't forget to put your Z next to it. So this is your answer. Four Z squared minus 7 Z plus three. So all of these right from side by side. So we have four Z squared. -7 Z plus three. And that's our answer. So I'm going to type it in. So I'm going to come here and we're going to type in four. Z and I'm going to hit this little exponent box for the squared. And then hit the space bar to get out of this weird. So for Z squared minus 7 Z and then a plus three. And we're going to hit submit and is correct.