Question

Consider the equation x(y + 1) = x + 3 . Check whether x is directly or inversely proportional to y. [3 MARKS]

Answer 1

Statement of conditions for proportionality: 1 Mark
Solution: 2 Marks

We know that the condition for direct proportion is $\frac{x}{y}=constant$
and the condition for inverse proportion is xy = constant

Expanding the given equation we have,

xy + x = x + 3

xy = 3

So, x is inversely proportional to y.