X - the number of hats on Monday

So, he had 40 on Monday.
Answer:
there is no slope the answer is undefined
Step-by-step explanation:
the line in this case is a vertical line which would be an undefined line a horizontal line has a slope of zero.
the equation for slope is y^2-y^1/x^2-x^1
Is this finding area or what is it?
There are twelve inches in a ruler and a door is about 7-8 feet