Speed=distance/time
A line graph is used to compare two specific variables.
You first subtract two velocities at two different time intervals. This gives you a difference of velocity. Then you divide this by the time.
Line graph is used to show relationship between two variables.
shutter speed and lens aperture
Lots of the other letters of the alphabet are used for either constant numbers or variables that are based on certain formula. C for instance is the speed of light in a vacuum (a constant) m is normally used for mass (a variable). x and y were most likely used as they were letters least likely to be used for representation of anything else and so the idea stuck to use them as calculable variables. Hope this helps.
Usually there is only one comparison of two variables in calculating a speed.
There are used to encapsulate a relationship between two or more variables.
A diagram that shows how two variables are related is called a "scatter plot." It is a visual representation of the relationship between the two variables, often used to identify patterns or trends in the data.
A function.
Distance-wavelength lambda (λ) is measured in meters (m)Time- frequency is measured in Hertz (Hz)
You didn't provide the relationship between the two variables. If it is a constant-speed problem, use the formula distance = speed x time.
I have never seen the term 'symbolic' used in this way. There are 4 methods used to solve a system of linear equations in two variables. Graphing, Substitution, Elimination, and Cramer's Rule.