Answer:
The two factors are (x + 3) and (x - 8)
Explanation:
The given function is x² + b·x - 24
The difference between the factors = 11
The sign of coefficient b = Negative
Therefore, we have;
The factors as (x - c) and (x + d)
-b = d - c...(1)
d × (-c) = -24...(2)
(x + d) - (x - c) = 11
Which gives;
x + d - x + c = 11
∴ d + c = 11...(3)
From equation (3), we have;
d = -24(-c) = 24/c
d = 24/c
Substituting the value of d in equation (3) gives;
d + c = 24/c + c = 11
24/c + c = 11
∴ c² + 24 = 11·c
c² + 24 - 11·c = 0
c² - 11·c + 24 = 0
(c - 8)·(c - 3) = 0
c = 8 or 3
From d + c = 11, we have, d = 3 or 8
Given that -b = d - c, therefore c > d and c = 8, d = 3
Therefore, the two factors are (x - 8) and (x + 3).