we know that
A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form y=kx
where
k is the constant of proportionality or slope
In this problem
we have a proportional relationship between the land planted and the wheat produced
Let
l ----> number of acres
w ----> wheat produced
so
w=kl
take the point (1,50)
Find teh value of k
k=w/l
k=50/1=50
therefore the equation is equal to
w=50l
