Answer:

Step-by-step explanation:
Given

Required
Write in Standard Form
To start with; the two monomials have to be multiplied together;


Split the numerator and the denominator

Multiply Like terms

Divide 9 by 3 to give 3

Divide n³ by n to n²

Split fraction

From laws of indices;

becomes

Multiply all together

Translate to english and i can help
The answer of all of this is 18 because 18.1 months so if you do the math you get 18-7x+20^2