The Slope-Intercept form of an equation of a line is:
Where "m" is the slope of the line and "b" is the y-intercept.
According to the information given in the exercise, each hour the temperature rises 6 °F, then you can identify that the slope is:
Knowing that the temperature at sunrise is 42 °F, you can identify that the value of "b" is the following:
Then, the equation that models the temperature "y" (in degrees Farenheit) after "x" hours, is:
In order to graph it, you can also find the x-intercept. By definition, when the line cuts the x-axis, the value of "y" is:
Substituting this value into the equation and solving for "x", you get:
Knowing the y-intercept and the x-intecept, you can graph the equation.
The answers
- Equation:
- Graph: