WEBVTT
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Actually, what I want to do is I want to show you guys how to solve a one step equation
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using the addition property of Equality.
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First thing we've got to remember, the addition property quality states that whenever we add
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a number onto a one side equation, we add it onto the other side equation, the equation
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is going to remain the same.
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So when I'm solving an equation, I'm going to go through four different steps that I'd
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like you guys to go ahead and complete.
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The first step, and this is just going to help you guys to be able to understand how
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to solve the problem.
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The first step is to circle out a variable.
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And the reason why I'm telling you to circle the variables is because you need to remember
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that the variable is what you're solving for.
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And when I say solve, you're trying to solve for what is the value of this variable.
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So you're going to circle your variable.
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So that's going to be your step one.
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Then step two is now we need to figure out what is happening to this variable.
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Now since this is only one step equation, we only know there's one operation that's
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happening to this variable.
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So the operation that's happening to the variable is going to be subtraction.
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We notice that 25 is subtracted from g.
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So we first start with a variable and then we need to divide operation, which here is
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subtraction.
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So the reason why I'm defining subtraction as what's happening to the variable is because
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what I need to do to get my variable to solve my variable, I need to use the inverse operation
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or a lot of times it's called the opposite operation.
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And what we use is, and we notice the opposite of subtraction is going to be addition.
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Now we need to use inverse operation.
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Is that on the screen so?
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Okay.
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So we have used inverse operation.
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So the inverse operation of subtraction is going to be addition.
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Now knowing my addition property of equality, I can add a 25 of all sides and my equation
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will still remain mathematically correct.
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So now I have 113 plus 25, which would be called 100 and 38 equals g.
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And then I notice my negative 25 plus 25, that's going to cancel it to give me zero.
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So therefore, really do I need to write zero?
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No.
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So therefore my answer is 138 equals g.
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And I use my inverse operation.
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And then for my last step, just to make sure I can check my answer.
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So for step number four, I know that 138 equals g.
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So now I'm going to plug that back into my original equation.
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So let me say 113 equals 138 minus 25.
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I go into double check.
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So that is how you solve a one step equation using addition property of equality.