Explanation

To factorize 10y² - 3y - 1:

Look for two numbers whose product is 10 × (-1) = -10 and whose sum is -3.

These numbers are -5 and 2.

Rewrite the middle term:

10y² - 5y + 2y - 1

Now, factor by grouping:

(10y² - 5y) + (2y - 1)

5y(2y - 1) + 1(2y - 1)

Common factor (2y - 1):

(2y - 1)(5y + 1)