Given: x2 – 17x + 60 = 0
On splitting the middle term –17x as – 12x – 5x, we get:
x2 – 12x – 5x + 60 = 0
x(x – 12) – 5(x – 12) = 0
(x – 12) (x – 5) = 0
We know that if the product of two numbers is zero, then at least one of them must be zero.
Thus,
x – 12 = 0 or x – 5 = 0
x = 12 or x = 5
Therefore, the solution of the given equation is x = 12, 5.