Question

Consider the function f(x) = x2 + 12x + 11. x-intercepts?

Answer 1

The x-intercepts of this function are -11 and -1.

The easiest way to find the intercepts of this graph is by factoring. To factor a quadratic, we look for factors of the last number, that add up to the middle number. Below are the factors of the last number.

1 and 11

-1 and -11

Now we look for one that adds up to positive 12.

1 and 11

-1 and -11

Since these two add up to the middle number, we can use them in parenthesis with x + and factor. If there was not a pair, we would then have to use the quadratic equation.

f(x) = (x + 1)(x + 11)

Now to solve for the x-intercepts, we set each parenthesis equal to 0 and solve for x.

x + 1 = 0

x = -1

x + 11 = 0

x = -11

Answer 2

Answer:

x intercept: (-1,0) & (-11,0)

y intercept: (0,11)

Step-by-step explanation: