Solve Quadratic Equationsby Factoring - Example 2
Solve Quadratic Equationsby Graphing - Example 2
Solving Quadratic Equationsby Completingthe Square - Example 2
The Discriminant - Example 2
Adding Subtracting And Multiplying Complex Numbers - Example 3
Liberty University
Solve Quadratic Equations Algebraically - Example 2


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inequality. X squared minus three X minus 18 is greater than eight. We're gonna work it out. Ouch. Brickley. And we're gonna do this. We're gonna go ahead and factored out and someone factor out. I'm looking for two factors of negative 18 that are going to give me negative three. And those two factors or negative six and positive three. So I have X minus six and X plus three with equal zero. So now that I've got my factors, let's go ahead and work those out. So that would be X minus six equals zero and X plus three equals zero. So we would add six. So X equal six and we would subtract three x equals negative three. So now that we have that, let's go ahead and do a number line to determine what our actual solution would be. So are right now we have X equals negative three and X equals six. So, in our number line, that's what we want. We want negative three, and we won't. Six. We're going to buy this number line. I will go and put zero there into three sections. We're gonna have it first where X is less than negative three. We're gonna have it where X is greater than six. And we're gonna have the section in the middle where negative three is less than X, which is less than six. And we're gonna see which is true. We're gonna test some numbers, so X is less than negative three. So let's test negative four. So that means we're gonna have negative four squared minus four minus three times negative four, minus 18 and that's going to give May 10. And we're saying 10 is greater than zero and that statement is true. So because we're X is less than negative three. Let's check and make sure X is greater than six. But we may not have to check this metal section, so let's do this. X is greater than six section. So let's just pick a number greater than six. I'm just gonna do seven. Where you gonna go? One name number larger. So that's gonna be seven squared minus three times seven minus 18. And when I plugged that in, I get 10 is greater than zero. And that statement is true. And because that statement is true, that means that both of these are true. So that means that my solution is eggs is less than negative. Three or X is greater than six.

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