Question

What does the question mark stand for in the following when you factorise:

12x2 + 3xy = 3x(?+y)

Answer 1

Explanation:

Since 12x² = 3x * 4x and 3xy = 3x * y,

12x² + 3xy = (3x)(4x) + (3x)(y) = 3x(4x + y).

Hence the question mark stands for 4x.