Question

Please answer this and Explain it properly
please...........
If the HCF of the polynomials (x + 4)(2x2 + 5x + a) and (x + 3)(x2 + 7x + b) is (x2 + 7x + 12) then
6a + b is
(A)-6
(B) 5
(D) - 5
(C) 6​

Answer 1

Answer:

Option(A) : -6

Given,

HCF = (x + 4)(2x^2 + 5x + a) and (x + 3)(x^2 + 7x + b) is (x^2 + 7x + 12)

To Find,

Value of 6a + b is = ?

Solution,

GCD = x² + 7x + 12 = (x + 3)(x + 4)

Polynomials are,

1.

f(x) = (x + 4)(2x² + 5x + a)

Apply Factor theorem,

f(-3) = 0

==> 0 = 1 * (18 - 15 + a)

==> 0 = 18 - 15 + a

==> a = -3

2.

g(-4) = 0

==> 0 = (-1) * (16 - 28 + b)

==> 0 = b - 12

==> b = 12

Value of 6a + b,

==> 6(-3) + (12)

==> -18 + 12

==> -6

Result,

Value of 6a + b = -6.

#Hope my answer helped you.

Answer 2

Sry dude..didn't find any other way to communicate with you.....

I just wanted to wish for ur exam...

All the best......

and by the way i think tht the answer is

option (a)...

i know u dont need them anymore but....xD..

#AVicci lives on....

#Heavy metal rocks...(pun intended)..xD