Direct and inverse proportion · Optional extension
L065 · Allow 10–15 minutes for learners ready to move on. Answers are available after an attempt.
Stretch
y is inversely proportional to x². If y=12 at x=2, find y at x=4.
Reveal a worked check after attempting
y=k/x², k=48; y=3.
Deep challenge
A graph through the origin appears curved upward. Can y be directly proportional to x? Explain.
Reveal a worked check after attempting
Direct proportion y=kx is a straight line through the origin; a curved graph does not fit.