Answer:
The amount of cents in the bank is:
![7x^2 +6x +3](https://img.qammunity.org/2020/formulas/mathematics/college/vg5rfwmu38wotoi6z9g1t4mcd9zl4723g3.png)
Explanation:
To answer this question you must divide the polynomial of degree 3 between the polynomial of degree 1.
That is, we must perform the following operation:
![(21x^3 + 18x^2 + 9x)/(3x)](https://img.qammunity.org/2020/formulas/mathematics/college/m2jiqia5li4o2hlzft8831ci0ruhc3m37y.png)
To make this division we must divide each term of the main polynomial by 3x.
![(21x^3)/(3x) = 7x^2](https://img.qammunity.org/2020/formulas/mathematics/college/uncq80lpdxblvqof85wgwm3b9pyihu696s.png)
![(18x^2)/(3x) = 6x](https://img.qammunity.org/2020/formulas/mathematics/college/ikfd31tzosoz539wio66s0wnbeajf41zjd.png)
![(9x)/(3x) = 3](https://img.qammunity.org/2020/formulas/mathematics/college/6g80ze475y4ilzlwvyxps3khfxdcylytan.png)
Finally, the result is:
![7x^2 +6x +3](https://img.qammunity.org/2020/formulas/mathematics/college/vg5rfwmu38wotoi6z9g1t4mcd9zl4723g3.png)