Answer:
5 amperes will produce the maximum power of 300 watts.
Explanation:
The general form of a quadratic function presents the function in the form
![f(x)=ax^2+bx+c](https://img.qammunity.org/2020/formulas/mathematics/middle-school/7ocbn4l6fhq9d44wxaeha6t60ls5h9hg74.png)
The vertex of a quadratic function is the highest or lowest point, also known as the maximum or minimum of a quadratic function.
We can define the vertex by doing the following:
- Identify a, b, and c
- Find, the x-coordinate of the vertex, by substituting a and b into
![x-coordinate =-(b)/(2a)](https://img.qammunity.org/2020/formulas/mathematics/high-school/caqoeermaqrsqysrscwneuj2zk2z7o2pj1.png)
- Find, the y-coordinate of the vertex, by evaluating
![y-coordinate =f(x-coordinate )=f(-(b)/(2a) )](https://img.qammunity.org/2020/formulas/mathematics/high-school/b7zzeb9dkr2lf8wobfu9n2dqjehezud1nz.png)
We know that the power generated by an electrical circuit is modeled by
![P(c)=-12c^(2)+120c](https://img.qammunity.org/2020/formulas/mathematics/high-school/vow2kofc198coa42dqddjbc8cgfyieopqt.png)
This function is a quadratic function.
To find the current that produce the maximum power you must
a = -12 and b = 120
- Find, the maximum current of the vertex, by substituting a and b into
![maximum-current =-(b)/(2a)](https://img.qammunity.org/2020/formulas/mathematics/high-school/fmlmg2d9dgrbd3l5x4h2jj3dhe5w0gj5sz.png)
![maximum-current =-(120)/(2(-12))\\\\maximum-current = 5](https://img.qammunity.org/2020/formulas/mathematics/high-school/g889jtdfbi7mbh0k6pklsic0ur4vjlgcgk.png)
- Find, the maximum-power, by evaluating
![maximum-power =P(maximum-current)=P(-(b)/(2a) )](https://img.qammunity.org/2020/formulas/mathematics/high-school/ibs1rz26i0pauak8agd4gawuvw7kj2uvqm.png)
![P(5)=-12(5)^(2)+120(5)=300](https://img.qammunity.org/2020/formulas/mathematics/high-school/4n9h675z40w1rix6e60x1k330psovdie0h.png)
5 amperes will produce the maximum power of 300 watts.
We can check our work with the graph of the function
and see that the maximum is (5, 300).