Question

if (x - 4) is the HCF of x square - 8 x + 15 and x square minus kx + 1 then what is k?​

Answer 1

(x-4) is HCF i.e. a factor of both equations

∴ The equations must get satisfied for x=4

Also, when x=4, both equations are equal in value.

Putting x=4 in both equations

42 - 8(4) + 15 = 42- k(4) +1

∴ 31-32 = 17- 4k

∴ k=4