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Krzysztof solved the quadratic equation 11x^2+44x-99=0 by completing the square. In the process, he came up with the equivalent equation (x+r)^2 = s,where r and s are constants.What is r+s.

 Jan 23, 2021
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11x^2  + 44x   - 99   = 0           divide through  by  11

 

x^2  + 4x   -  9    = 0               add 9 to  both sides

 

x^2 + 4x    = 9                       take 1/2 of 4 = 2.....square this =  4   add to  both sides

 

x^2 + 4x  + 4   =  9  + 4       factor the  left side,  simplify the right

 

(x + 2)^2  =  13

 

r = 2      s  =  13

 

r +  s  =    15

 

cool cool cool

 Jan 23, 2021

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