Neil and Chris were trying to solve the quadratic equation

x^2 + bx + c = 0.

Neil wrote down the wrong value of b (but his value of c was correct), and found the roots to be 1 and 6. Chris wrote down the wrong value of c (but his value of b was correct), and found the roots to be -1 and -4. What are the actual roots of x^2 + bx + c = 0?

matthewmacdell Mar 20, 2020

#1**+3 **

******* edited **** edited ***** **

Neil found 1 and 6 this means (x-1)(x-6) x^2 - 7x + 6

Chris found -1 and -4 this means (x+1)(x+4) = x^2 + 5x + 6

If the correct values are in red then the equation must be x^2 + 5x + 6 which factors to (x+3)(x+2) roots -3 and - 2

ElectricPavlov Mar 20, 2020

#2**+1 **

thanks !! but i entered 2 and 3 as a list, and it marked me wrong. do you know what's up?

matthewmacdell
Mar 20, 2020

#3

#4

#5