Factor
1. a^2 - 5a - 6
2. b^2 - 7b + 12
3. 3x^2 + 2xy - y^2
4. 3y^4 - 2y^2 - 5
5. a^2b^2 - 7ab + 10
6. y^2 - xy - 56x^2
7. 4x^2+ 8xy - 60y^2

1. a²-5a-6
    look for the factors of the last number without a variable so that it's sum is      the coefficient of the number which has the variable power 1
    a²+a-6a-6
    then factor by grouping.
    a(a+1)-6(a+1)
    (a-6)(a+1)
so do that to others too try it yourself. if you still need help let me know!!!

21, i'm pretty sure it's right lol