Answer:
f(x) = -22.45x^2 + 92.38x + 1.86
Because the points on the scatter plot show an increase in concentration from 0 hours through 2 hours and a decrease from 2 hours through 4 hours, the relationship shown is best modeled using a quadratic function.
Let's look closely at the two quadratic function choices to determine the key features of their graphs.
Because the coefficient of its x^2 -term is negative, the graph of f(x) = -22.45x^2 + 92.38 + 1.86 will be concave down and have a maximum value.
Because the coefficient of its x^2 -term is positive, the graph of f(x) = 22.45x^2 + 92.38 + 1.86 will be concave up and have a minimum value.
Because the scatter plot shown has a concave down trend, the function that best describes the relationship shown is:
f(x) = -22.45x^2 + 92.38 + 1.86
Step-by-step explanation: