the answer would be -8<x<2
Answer:



Step-by-step explanation:

They wanted to complete the square so they took the thing in front of x and divided by 2 then squared. Whatever you add in, you must take out.

Now we are read to write that one part (the first three terms together) as a square:

I don't see this but what happens if we find a common denominator for those 2 terms after the square. (b/2a)^2=b^2/4a^2 so we need to multiply that one fraction by 4a/4a.

They put it in ( )

I'm going to go ahead and combine those fractions now:

I'm going to factor out a -1 in the second term ( the one in the second ( ) ):

Now I'm going to add (b^2-4ac)/(4a^2) on both sides:

I'm going to square root both sides to rid of the square on the x+b/(2a) part:


Now subtract b/(2a) on both sides:

Combine the fractions (they have the same denominator):

Answer:

Step-by-step explanation:
Where p is the distance from focus to vertex, the equation of the parabola with focus at (0, p) is ...

Your parabola has p=9, so the equation is ...

The answer is D! This shape is a pentagon and has 3 180° angles. 3x180 is 540.