How to Solve Quadratic Equations with the Square R Video

How to Solve Quadratic Equations with the Square Root Rule

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How to Solve Quadratic Equations with the Square R -

Mathematical tutorial: this tutorial will show you how to solve quadratic equations with the square root rule.

How to Solve Quadratic Equations with the Square R -

Mathematical tutorial: this tutorial will show you how to solve quadratic equations with the square root rule.

Added: 9/17/09

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How to Solve Quadratic Equations with the Square R for dummies dummies education tips math help math homework help math tips mathematics quadratic equations solve quadratic equations square root rule tech help wiley

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By: Guest More than a year ago

the -7 in the video should be in parentheses because it would be -49 if not so you need() or people will be getting it wrong

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By: Guest More than a year ago

-1

I was taught this in Grade 9. GTFO

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By: Guest More than a year ago

best explanation

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How to Solve Quadratic Equations with the Square Root Rule

When a quadratic equation consists of just a squared term in a constant, you solve the equation by using the square root rule. If the square of variable is equal to the number K, then the variable is equals to the principle square root of K or its opposite. You use this rule to solve some special quadratic equation by one squared B = 0. They start out looking like AXsquared + C=0 but the C is usually negative and it's inverse gets added to each side of the equation so the equation looks like AXsquared=C. Here are a few examples. Let's solve for X and X2=49. Using the square root rule, X= plus or minus the square root of 49 which equals plus or minus seven. And this checks out because seven squared is equals to 49 and minus seven squared is also equals 49. Here's another one. Solve for M in three Msquared plus four=52. This one isn't quite ready for the square root rule. First, you have to add minus four to each side. So, three Msquared=48. Now, divide each side by three and Msquared=16. So M=plus or minus the square root of 16 which is plus or minus four. Solve for P for this one. First, add minus 11 to each side to get Psquared=minus four but wait, what number times itself is equal to minus four? The answer is none that you can imagine. Actually, mathematicians have created imaginary numbers so that these numbers can be finished but right now, we're only concerned with less heady numbers. So this problem doesn't have any answer. If you're looking for a real number. All right, no tricks on this one but the answer may suprise you. Let's solve for Q. We actually end up with two completely different answers, not one number and its opposite. We use the square root rule first to get Q+3= plus or minus the square root of 25 which is plus or minus five. Now we have two different linear equations to solve. Q+3=5 and Q+3=(-5). Subtracting three in each side of each equation gives you Q=2 and Q=(-8). THis one definitely needs to be checked. Putting in the two for Q=25 and putting in the (-8) for Q also equals to 25. So yes, they all work. Now, you won't be boxed in when you apply the square root rule in algebra.

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When a quadratic equation consists of just a squared term in a constant, you solve the equation by using the square root rule. If the square of variable is equal to the number K, then the variable is equals to the principle square root of K or its opposite. You use this rule to solve some special quadratic equation by one squared B = 0. They start out looking like AXsquared + C=0 but the C is usually negative and it's inverse gets added to each side of the equation so the equation looks like AXsquared=C. Here are a few examples. Let's solve for X and X2=49. Using the square root rule, X= plus or minus the square root of 49 which equals plus or minus seven. And this checks out because seven squared is equals to 49 and minus seven squared is also equals 49.

Here's another one. Solve for M in three Msquared plus four=52. This one isn't quite ready for the square root rule. First, you have to add minus four to each side. So, three Msquared=48. Now, divide each side by three and Msquared=16. So M=plus or minus the square root of 16 which is plus or minus four. Solve for P for this one. First, add minus 11 to each side to get Psquared=minus four but wait, what number times itself is equal to minus four? The answer is none that you can imagine. Actually, mathematicians have created imaginary numbers so that these numbers can be finished but right now, we're only concerned with less heady numbers. So this problem doesn't have any answer. If you're looking for a real number. All right, no tricks on this one but the answer may suprise you. Let's solve for Q.

We actually end up with two completely different answers, not one number and its opposite. We use the square root rule first to get Q+3= plus or minus the square root of 25 which is plus or minus five. Now we have two different linear equations to solve. Q+3=5 and Q+3=(-5). Subtracting three in each side of each equation gives you Q=2 and Q=(-8). THis one definitely needs to be checked. Putting in the two for Q=25 and putting in the (-8) for Q also equals to 25. So yes, they all work.

Now, you won't be boxed in when you apply the square root rule in algebra.

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