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What are the solutions to the quadratic equation below x^2+20x+100=7​

User Kandra
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1 Answer

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First you must have the quadratic equal to zero. In order to do this you must subtract 7 to both sides

x^2 + 20x + (100 - 7) = 7 - 7

x^2 + 20x + 93 = 0

Now you must find two numbers who's sum equals 20 and their multiplication equal 93

Are there any? NO!

This means that you have to use the formula:


\frac{-b±\sqrt{b^(2) - 4ac} }{2a}

In this case:

a = 1

b = 20

c = 93


\frac{-(20) plus/minus\sqrt{20^(2) - 4(1)(93)} }{2*1}


(-20 plus/minus√(400 - 372) )/(2)


(-20 plus/minus√(28) )/(2)

^^^We must simplify √28

√28 = 2√7

so...


(-20 plus/minus 2√(7) )/(2)

simplify further:


-10 plus/minus\sqrt{7

-10 + √7

or

-10 - √7

***plus/minus = ±

Hope this helped!

~Just a girl in love with Shawn Mendes

User Michael Lumbroso
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