What fraction of the pizza did group C eat? Use words and pictures to explain your answer.

We want a line that passes through the point (4, 7/2)

and we have no other information of this line, so we can not fully find it, but we can find a general line.

We know that a line can be written as:

y = a*x + b.

Now we want that, when x = 4, we must have y = 7/2.

7/2 = a*4 + b

b = -a*4 + 7/2

Then we can write this line as:

y = a*x - a*4 + 7/2.

Where a can take any value, and it is the slope of our line.