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

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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

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

User Chrisby
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