Answer:
1. 2(a^2 + 3a + 9)
2. 5(x^2 - 1)
3. 3(t + 8)(t - 2)
4. n(4 - n)
Explanation:
For 1, you can only factor out the constant from each.
For 2, you can also only factor out the constant, but remember that you include the 1 when dividing 5 by 5.
For 3, you can factor out the constant and the variables.
For 4, you can only factor out the variable.