What are the zeros of the function f(x)=x2+2x−35 ? enter your answers in the boxes. the zeros of f(x)

Remark
There are a couple of things you can do to help you factor these questions. When you factor them, that will give you the zeros.

The first thing is to write down all the factors of 35. There are only 4. 35 and 1 and 7 and 5. 

When you have done that you should notice that the number in the middle term is quite small. That means that the factors of 35 should be quite close together. 1 and 35 are not close together.

So the factors you use are 7 and 5, but which is plus and which is minus (you need one of each because 35 is minus.

So far what you have is
(x   7)(x   5) The larger the value of the factors is used for the sign. 7 > 5 so 7 is plus.

Finally
(x + 7)(x - 5) =0

And the roots are
x + 7 = 0
x = - 7

x - 5 = 0
x = 5

Roots (5,0)(-7,0)

The graph is below to show agreement.