1. 5x²-45

2. ax²-4a.

3. 3x²-75a²

4. - 2ay²+2a³

5. 5a²+10ab+5b²

6. ax²-2axy+ay²

7. - 6a²+12ab-6b²

1. 5 (х^2-9) = 5 (х-3) (х+3)

2. а (х^2-4) = а (х-2) (х+2)

3. 3 (х^2-25 а^2) = 3 (х-5 а) (х+5 а)

4. 2a (-y^2+a^2) = 2a (a-y) (a+y)

5. 10ab + (5a^2-5b^2) = 10ab+5 (a-b) (a+b)

6. a (x^2-2xy+y^2) = a (x-y) ^2

7. 12ab + (-6a^2-6b^2) = 12ab-6 (a^2-b^2) = 12ab-6 (a+b) (a-b)