Solution:
Given that we have to factor -3y - 18
Use the distributive property,
a(b + c) = ab + bc
From given,
-3y - 18
Factor out the greatest common factor of 3 and 18
The factors of 3 are: 1, 3
The factors of 18 are: 1, 2, 3, 6, 9, 18
Then the greatest common factor is 3
Factot out 3 from given expression
-3y - 18 = 3( - y - 6)
Or else we can rewrite as,
-3y - 18 = -3(y + 6)
Thus the given expression is factored