Question

(i) (x + 3) is a factor of (5x + 4)3 – (3x + k)3.​

Answer 1

• Answer:

x+3=0

x= -3

(5x+4)3 -(3x+k)3=0

15x+12-6x+3k=0

9x+12+3k=0

9(-3)+12=-3k

(-27)+12= -3k

-15= -3k

k=15/3

k=5