Solve the polynomial inequality and graph the solution set on a number line. Express the solution set in interval notation.
x^2 - 4x - 12

Question

Solve the polynomial inequality and graph the solution set on a number line. Express the solution set in interval notation.
x^2 - 4x - 12 <= 0

anonymous · Answer

First, you can split $$x^2 - 4x - 12$$ up into two linear terms. Solve the inequality for each of the two terms.

anonymous · Answer

by factoring

anonymous · Answer

Yes, find two numbers that multiply to give 12 and add or subtract to give 4.

anonymous · Answer

okay so I get (x-6)(x+4)

anonymous · Answer

Almost, but not quite.   (x-6)(x+2)

anonymous · Answer

oops (x+2)

anonymous · Answer

Now solve the inequality for each of those two terms.

anonymous · Answer

that is where I get lost

anonymous · Answer

my solution sets are 
a. (6, infinity)
b. (-infinity, -2)
c. (-infinity, -2)(6, infinity)
d. (-2,-6)

anonymous · Answer

my stupid computer keeps freezing up

anonymous · Answer

First set the terms equal to zero and solve for x. You will get two solutions.

anonymous · Answer

so place 0 in x

anonymous · Answer

No, don't place x in for zero. You have this:
$$x - 6 = 0$$$$x + 2 = 0$$
Solve each of these.

anonymous · Answer

so 
x= 6
x= -2

anonymous · Answer

That's correct so now you have a numberline that looks thusly: |dw:1342811332171:dw|