Answer:

Step-by-step explanation:
Let
x ----> the length of Zach's car
y ----> the length of Ginny's car
we know that
The sum of the lengths of both cars is 30 inches
so
----> equation A
Ginny's car is 2 more than 3 times the length of Zach's car
so
----> equation B
substitute equation B in equation A

100p? if you would like to explain what the variable p is i could help out
Extrapolation is the process by which a value is estimated by using a previously known set of numbers. Interpolation is where a value is estimated between two known values. In this case, if you wanted to predict the value of the y-variable when the x-variable is 15, you would be extrapolating beyond the known data-set.
Now, assuming is a vertical parabola, so the squared variable is the "x", let's do some checking.