JAMB 2014 · UTME · Q13

Factorize $2y^2 - 15xy + 18x^2$ .

Worked solution (try it first)

Find two terms with product $2 \times 18x^2 = 36x^2$ and sum $-15x$ : they are $-12x$ and $-3x$ .
Split the middle term: $2y^2 - 12xy - 3xy + 18x^2$ .
Group in pairs: $2y(y - 6x) - 3x(y - 6x) = (2y - 3x)(y - 6x)$ , option C.