For this case we have that by definition, the line equation of the slope-intersection form is given by:

Where:
m: It's the slope
b: It is the cut-off point with the y axis
According to the statement we have:

Thus, the equation is of the form:

We substitute the given point and find "b":

Finally, the equation is of the form:

Answer:

-5t2 + 40t = 0
5t(-t+ 8) = 0
5t = 0 or t = 8
C is 23 because if you get all rhe numbers and measure thats your answer. I think i might be wrong. if I am then sorry