Identify the quadratic function with a parabola that opens downward.
y = -4x + x2
y = 6x2 – 3x
y = x2 – 13x -2
y = x – 3x2 + 10

Question

Identify the quadratic function with a parabola that opens downward. 
    y = -4x + x2 
   y = 6x2 – 3x 
   y = x2 – 13x -2 
   y = x – 3x2 + 10

anonymous · Answer

The simplest way to explain it is that the quadratic term "dominates" the linear term. The quadratic term is the one with the ^2. Linear is the term with just the 'x'. So you just need to find the x^2 term with the negative on it.

anonymous · Answer

i got the third one am i right?

anonymous · Answer

No, in the third one the quadratic term is (+)x^2

anonymous · Answer

so it would be the first?

anonymous · Answer

No, there the quadratic term is (+)x^2 also
They're just rearranging the terms to throw you off. The order doesn't matter. You just need to hunt for the quadratic term w/ the (-) on it.

anonymous · Answer

ahhh so the second one

anonymous · Answer

Negative, there the quadratic term is (+)6x^2

anonymous · Answer

4th?

anonymous · Answer

sooo confusing

anonymous · Answer

Look at all of the ^2 terms in all of those. Which one has the (-) in front of it.

anonymous · Answer

the 4th

anonymous · Answer

Here, let me circle the quadratic terms for you.

anonymous · Answer

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