I’m assuming you want to work out the area
area = length x width
area = 10 x 8
area = 80 inches^2
Do you have a picture with the question?
To be a function each different x value would have a different Y value.
First one is a function, there are no repeated Y values.
The second one is a function.
Third one is not a function because it has two identical Y values with different x values.
The fourth one is a function.
The answer is (4x20) + (4x4) which equals 96
