G 1) a2 + 3a - 40 = 0.

solving quadratic equations

The solution set is {-8, 5}.

Step-by-step explanation:

a^2 + 3a - 40 = 0.

We need 2 numbers whose product is - 40 and whose sum is + 3.

They would be + 8 and - 5, so we have the factors:

(a + 8) (a - 5) = 0

Now either a + 8 = 0 or a - 5 = 0, so:

a = - 8 or 5.