The slope intercept form of the equation of a line is given as:
y = mx + c
where m = the slope of the line
c = the y - intercept of the line
1) Two line are parallel if they have the same slope
That is:

2) Two equations are perpendicular if the slope of one is the negative inverse of the other.

3) Two equations are coincidental if they have the same slope and the same y intercept
There are 180 school days in a year. How many school days are in 5 years?
If we know that there are 180 school days in 1 year, we can multiply 180 by 5 to get our answer of how many school days are in 5 years.
900 school days in 5 years.
Here is the answer lmk if you need clarification