Question 284904
The maximum y-value is the y-coordinate of the vertex.

Find the vertex in the form (x,y) and then write down the y-value.

Can you take it from here?

Do you know how to find the vertex?

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You stated:

"No, I don't understand how to find the vertex if I am not given any points for "a" or "b" (since I'm supposed to use x = -(b/2a), right?)"

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The first thing to do is find the x value using -b/2a as you said.

Let a = 2, b = 4 from your function.

x = -b/2a

x = -4/2(2)

x = -4/4

x = -1....This is the x coordinate (x-value) of the vertex.  We can now find the y-value (also called y coordinate) by replacing every x you see in your function with -1 and doing the math.

y = 2x^2+4x+1

Let x = -1

y = 2(-1)^2 + 4(-1) + 1

y = 2 - 4 + 1

y = -2 + 1

y = -1

The y-value is, in this case, the same as the x-value, which is -1.

The maximum y-value is -1.

By the way, this is a parabola that opens upward (looks like a big letter U) with vertex at the point (-1,-1).

Got it?