A quadratic function models the profit of the company and the maximum/minimum value of the quadratic function occurs on its vertex.
The given function is:

The equation is already in standard form, the vertex of the parabola as seen from the equation is (5,12)
This mean if the company sets the price of socks to $5 they will earn a maximum profit which is $ 12 million
Using the percentage concept, it is found that 40% of Alberto’s income is used to pay for his rent and groceries.
<h3>What is a percentage?</h3>
The percentage of an amount a over a total amount b is given by a multiplied by 100% and divided by b, that is:

In this problem:
- Alberto’s monthly income is $3,200, hence b = 3200.
- He spends 896 + 384 = $1280 in rent and groceries, hence a = 1280.
Then, the percentage is given by:

More can be learned about the percentage concept at brainly.com/question/10491646
Any line can be graphed using two points. Select two x x values, and plug them into the equation to find the corresponding y y values. Any line can be graphed using two points. Select two x x values, and plug them into the equation to find the corresponding y y values.