AMO 2024 – Secondary 2 (Grade 8) Question 2

Points $A,B$ lie on $f(x)=x^2-4x-12$. Their $x$-coordinates are 1 and 5 respectively. Where does line $AB$ meet the $y$-axis? Clarification: the source omits the letter x before “coordinate” for B; the intended x-coordinate is used.