Find the turning point of y=4x^2-8x-5

[footprints]

$$y=4x^2-8x-5$$ Find the coordinates of the turning point of the curve. Where do I even start?

 

[Hurkyl]

With the definition of turning point.

 

[footprints]

I don't know that.

 

[Hurkyl]

Well, then, that's where you need to start. What does your book have to say, or your notes?

(Incidentally, what level math is this?)

 

[footprints]

My book doesn't say anything about the definition of a turning point. I'm in grade 9.

 

[danne89]

If you mean the minimi/maximi-point of the curve, you can set the derivate equal to zero and solve. Wait a minute, it must be an another way... Try to completting the square on the function...

 

[Hurkyl]

Where did you see the problem?


If I had to guess what it meant, I would say the point where the graph of the polynomial stops going downwards and starts going upwards. Since it's a parabola, that would be its vertex.

 

[footprints]

Try to completting the square on the function

Since it's a parabola, that would be its vertex.

Oh Yes! Now that you guys mention that, I know what to do now Thanks!