WAEC 2023 · Paper 1 · Q13

Find the quadratic equation whose roots are $\frac23$ and $-\frac34$ .

Worked solution (try it first)

Roots $\frac23$ and $-\frac34$ give the factors $(3y - 2)$ and $(4y + 3)$ , cleared of fractions.
Expand: $(3y - 2)(4y + 3) = 12y^2 + 9y - 8y - 6$
$= 12y^2 + y - 6$ .
So the equation is $12y^2 + y - 6 = 0$ , option C.