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Write down the quadratic equation whose roots are x=-7 and x=-1, and the coefficient of x^2 is 1.

Enter your answer in the form "x^2 + bx + c = 0".

 Mar 6, 2022
 #1
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The easiest way to solve this is to use Vietas. The sum and products of the roots are -8 and 7, respectively. 

 

We know the sum is \(-b\over a\). We also know a = 1, so b must be 8. 

 

We also know the product is \(c \over a\). Because we know a = 1, c must be 7. 

 

This means that the quadratic is \(\color{brown}\boxed{ x^2 + 8x+ 7}\)

 Mar 6, 2022

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