Question

20 POINTS !!!! The roots of the equation x^2+bx+c=0 are −4 and 2. Find b.

Answer 1

first, love the killua profile picture ! i love hunterxhunter i am currently on season 5, episode 44 or 45 aka 119 or 120 but anyways,

answer:

b = 2

step-by-step explanation:

because its roots are -4 and 2,

and a = 1 [The coefficient of $x^2$] we know that $x^2 + bx + c = (x - (-4)) (x-2)=(x+4)(x-2) = 0.$

using the distributive property we get,

$x^2 + 2x - 8 = 0.$

by equating coefficients (common strategy for partial fractions and undetermined coefficient method of solving ODE), we get b = 2 and c = -8 ( solved c just for fun guess :) ) .

hope this helps :)  

-audrey <3