Question

if alpha and beta are the zeros of the polynomial x2-6x+a find a if 3alpha + 3beta = 20

Answer 1

the following is ur answer:

Sum of zeroes = -B/A

Alpha + Beta = -(-6)/1 = 6

Alpha = 6 - Beta ... (1)

Putting (1) in 3alpha + 2beta = 20

3(6 - Beta) + 2(Beta) = 20

18 - 3Beta + 2Beta = 20

-Beta = 2

Beta = -2

Alpha = 6 - Beta = 6 - (-2) = 8

Product of zeroes = C/A

Alpha*Beta = a/1 = a

8/(-2) = a

a = -4