A rectangle of area y m^2 has sides of length x m and (Ax+B)m, where A and B are constants and x and y are variables. A graph of y/x against x is plotted. (250,214) & (50,74) lie on the same line.

(i) use your graph to estimate the value of A and of B ( I arrive at A=7/10 but B has 2 answers by using the 2 different coordinates)/
(ii) On the same diagram draw the straight line representing the equation y=x^2, explain the significance of the value of x given by the point of intersection between the two lines.

Question

A rectangle of area y m^2 has sides of length x m and (Ax+B)m, where A and B are constants and x and y are variables. A graph of y/x against x is plotted. (250,214) & (50,74) lie on the same line.

(i) use your graph to estimate the value of A and of B ( I arrive at A=7/10 but B has 2 answers by using the 2 different coordinates)/
(ii) On the same diagram draw the straight line representing the equation y=x^2, explain the significance of the value of x given by the point of intersection between the two lines.

mertsj · Answer

I thought I could solve this until I saw the part about drawing the straight line representing y = x^2.  Must be something here I know nothing about.