Complete the steps to solve the polynomial equation x3 – 21x = –20. According to the rational root theorem, which number is a potential root of the polynomial?

Zeroes : 1, 4 and -5.

Potential roots: .

Step-by-step explanation:

The given equation is

It can be written as

Splitting the middle terms, we get

Splitting the middle terms, we get

Using zero product property, we get

Therefore, the zeroes of the equation are 1, 4 and -5.

According to rational root theorem, the potential root of the polynomial are

Constant = 20

Factors of constant ±1, ±2, ±4, ±5, ±10, ±20.

Leading coefficient= 1

Factors of leading coefficient ±1.

Therefore, the potential root of the polynomial are .

n=9

step-by-step explanation:

7 times a number = 7n

decreased by 13 = 7n-13

same as is =

5 times the number = 5n

increased by 5 = 5n+5

7n-13 = 5n+5

2n=18

n=9