Question

If x+5 is a factor of polynomial p(x)=x3-20x+5k, then k equals
a) 5
b) 3
c) -5
d) -3
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Answer 1

Answer:

5

Step-by-step explanation:

x+5 = 0

x = -5

PUT THE VALUE OF X IN THE EQUATION

x³ - 20x + 5k = 0

-5³ - 20(-5) + 5k = 0

-125 + 100 + 5k = 0

-25 + 5k = 0

5k = 25

k = 25/5

k = 5