Which function has real zeros at x = 3 and x = 7? f(x) = x2 + 4x – 21 f(x) = x2 – 4x – 21 f(x) = x2 – 10x + 21 f(x) = x2 – 10x – 21

Option 3rd is correct

Step-by-step explanation:

As per the statement

We have a real zeros at x = 3 and x = 7

Since, the graph have zeros at x = 3 and x = 7 then;

By zero product property: if ab= 0 then a = 0 or b =0

⇒ and x -7 = 0

⇒

Let f(x) be the function has a real zeros at x = 3 and x = 7 then;

⇒

Using distributive property,

we have;

Combine like terms;

Therefore, the function has real zeros at x = 3 and x = 7 is,

i think the answer is b