I will not do your work for you. However, it helps to get started by knowing clearly what you need to know and what you need to do to solve problems like this:
In each question, you are asked to represent the relationship between two variables: how one can be expressed as a function of the other, and you need to establish how one changes with respect to the other.
If you're confused about the difference between the various forms (representations) of an equation (of a line), recall that:
the point-slope form for the equation of a line is formatted like this: $(y - y_0) = m(x - x_0)$:
$m$ = slope, $(x_0, y_0)$ is a particular point on the line.
the standard form of an equation of a line is: $ax + by = c$.
the slope-intercept form for the equation of a line is $y = mx + b$, again, with $m$ being slope, and $b$ represents the "$y$-intercept": the value of $y$ when $x = 0.$
You should become familiar with each form, because depending on the information you are given, one particular form may be needed. (E.g., if you're given a point on a line, and can determine the slope of a line, then point-slope form comes in handy!)
Once you have an equation in one form, then transitioning from one form to another requires some very basic algebra!
To get you started:
- What is your slope $m$ here? $\dfrac{\text{(Change in distance)}}{\text{(change in time)}} = m$.
From what you're given:
$\quad 12 = 12\cdot 1$
$\quad 24 = 12 \cdot 2$
continuing...
$\quad 36 = 12 \cdot 3$
$\quad\quad\;\;\vdots$
$\quad \;d = 12 \cdot h$
What does $12$ represent? This equation gives you the relation between $d$: distance traveled, and $h$: hours spent traveling. Now, simply put it in point-slope form, where $d$ is your "y" and $h$ is your "x": what is your starting point $(x_0, y_0)$?