WEBVTT mathematics/basic-math/pyo
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Welcome back to Educator.com.
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For the next lesson, we are going to go over writing expressions.
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Expressions again are math statements without an equal sign.
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We just have statements; we can use words.
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We can use different operations using numbers and variables to express some kind of statement.
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We are not going to use any equal signs.
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Some words that we can use to express adding--addition, plus, and more than.
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The minus, we have subtraction, minus, and less than.
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For this, we have multiplication, times, and product.
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You can also say multiplied or just multiplication.
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This is division, divided by, quotient.
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Remember this is probably going to be the hardest words to remember, product and quotient.
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Product, just remember that you are multiplying; quotient, you are going to be dividing.
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For these here, when you see the word than being used, you are going to actually switch the order.
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For example, if I say 2 more than X, we know that this right here means plus.
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But instead of saying 2 plus X, we are going to do a switch.
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That is every time you see the word than, you are going to switch the order.
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This is not 2 plus X; instead it is going to be X plus 2.
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Same thing for less than; if it is 2 less than X, it is going to be X minus 2.
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We are going to do some examples.
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We are going to write each as an expression; here it says 7 plus X.
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We know that plus means addition; this will be 7 plus X.
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That is it; that would be your answer; that is how you write an expression.
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The product of 4 and 3; when it says product, you are talking about multiplication.
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The product of something and something, you are going to be multiplying two things, this one and this one.
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That is going to be 4 times 3.
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That would be how you are going to write it as an expression.
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You can also simplify it if you can.
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We know that we can't simplify these because this is a number and this is a variable.
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So we are going to leave it like that; this is 4 times 3.
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If you want, you can also write this as that, simplified.
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Next one is C divided by 5 which is going to be C divided by 5.
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Also with division, you can write it like this.
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C divided by 5; this is also C divided by 5.
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This is a fraction but fractions are also division.
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They are also the top number divided by the bottom number.
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C divided by 5; you can write it either like this or like this.
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2 less than A; we know that less than means minus.
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But then here we see the word THAN.
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Whenever we see that, we are going to switch the order.
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It is not going to be 2 minus A; it is going to be A minus 2.
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This one comes first; this one is going to come last.
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If you write 2 minus A, that is actually going to be wrong.
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You have to make sure that you switch them; that becomes A minus 2.
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Let's do a few more; the sum of 10 and K.
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The sum you know is addition.
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We are going to be adding two things, this one and that.
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It is going to be 10 plus K.
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9 minus 10; this is... who knows?... minus.
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You are just writing it using the actual operations like that.
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This one again you can simplify because you are just subtracting two numbers.
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This is 9 minus 10; if you do 9 minus 10, it is not 1.
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It is actually going to be -1.
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Here we have a positive number.
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This minus is actually going to be part of this number.
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The sign actually goes with whatever is behind it.
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This becomes a -10; I can write a plus here.
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9 minus 10 is the same thing as 9 plus -10.
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This minus is the same thing as negative.
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If you want, you can change this to a plus problem and make that a negative right there.
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Here if you have 9 of something, say you have $9 but you need 10.
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Let's say you borrow 10; how much do you have left?--you have -1.
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12 more than Z; more than we know is plus.
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It is not going to be 12 plus Z because we see that word right there.
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We are going to switch them; it becomes Z plus 12.
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That we can't simplify; that is the answer for that.
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The quotient... quotient means divide... of P and 4.
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It is going to be P divided by 4.
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Or you can say P divided by 4 as a fraction.
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These we are going to write them using words.
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For the minus, for that operation, we can just say minus.
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We can say less than; we can say subtracted.
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Here I can say 10 minus 4; or if I want to use less than.
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Since you are using this word, remember you have to switch them; don't forget.
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You can say 4 less than 10.
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This one, 6 divided by 2; just write it out like that.
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Or you can say the quotient of something and something.
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That will be 6 and 2.
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Here we can use the word plus; we can use more than; or we can use sum.
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If I am going to use plus, then I just say B plus 3.
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I am going to use more than.
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Since you have to switch them, I am going to say 3 more than B.
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Or for the sum, I can say the sum of something and something.
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That will be, in order, B and 3.
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This one I can use times; I can say multiply; I can say product.
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It will be just be 5 times 5.
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If I am going to use product, then I have to say the product of something and something
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which will be 5 and 5, the product of 5 and 5.
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That is it for this lesson; thank you for watching Educator.com.