The diagram below shows a straight line graph where (x-y) is plotted against x^{2}y

Express y in terms of x

Solution:

gradient, m = 16-4/5-1

= 3

Y = 3X + C

sub x=1, y=4

4 = 3(1) + C

Y = 3X + 1——-(1)

sub Y = x-y, X = x^{2}y into (1)

x-y = 3x^{2}y + 1

x-1 = 3 x^{2}y + y

x-1 = y(3 x^{2} + 1)

x-1 = (x-1) / (3x^{2} + 1)