For this case we have the following expression:
![7x^(10) + 6x ^ 5 + 5](https://img.qammunity.org/2020/formulas/mathematics/middle-school/97t4x25nl53xss395mw0qhfj9yds73zlkv.png)
We must rewrite it quadratically:
By definition, a quadratic equation is of the form:
![ax ^ 2 + bx + c = 0](https://img.qammunity.org/2020/formulas/mathematics/high-school/sbletey3gjlyp38ihwqyczkdpf2s5u0sfw.png)
Now, suppose
![u = x ^ 5](https://img.qammunity.org/2020/formulas/mathematics/middle-school/g5i8er1bqjndlcl6t27rmse2hcpgk1ax9h.png)
Rewriting the given expression with the change of variable we have:
![7u ^ 2 + 6u + 5](https://img.qammunity.org/2020/formulas/mathematics/middle-school/nn1tw6900ufmtktnwjm7fb7enawezzlmes.png)
So, we have a quadratic expression.
Returning the change we have:
![7 (x ^ 5) ^ 2 + 6 (x ^ 5) +5](https://img.qammunity.org/2020/formulas/mathematics/middle-school/x9yklczxpkmrtcuwz09vxwyor95i3kwykh.png)
ANswer:
Option B