Question

What are the zeroes of f(x) = x^2 + 5^x + 6?

A. x = −2, −3
B. x = 2, 3
C. x = −2, 3
D. x = 2, −3

Answer 1

You can factor it by using a method of your choice. I'll just use guess and check, because it's the easiest in this situation (for me). I need two numbers that multiply to 6, and add up to 5. Those two number are 2 and 3. 2 * 3 = 6, and 2 + 3 = 5. So, I can write the above equation as follows in factored form:

`f(x) = (x+2)(x+3)`

Then it's pretty easy to recognize the zeros because I just have to solve for each parentheses by doing this:

`x + 2 = 0`

`x = -2`
and

`x + 3 = 0`

`x = -3`

So, your zeros are at -2 and -3. Your answer is A. If any step doesn't make sense, hmu!