Posted by Tonya on Friday, November 4, 2011 at 5:47pm.
How can I tell what direction this parabola open up
2x^2 +16x+24y224=0
We just started this in class today do I need to change this into another format

Algebra  MathMate, Saturday, November 5, 2011 at 8:04am
The leading coefficient tells the story.
The leading coefficient of a polynomial is the coefficient (number) associated with the variable of the highest power, in this case, x².
If the leading coefficient (2) is negative, it is concave down, i.e. it opens downwards. If the leading coefficient is positive, it is concave up.
An easy way to remember is the concavity follows the same direction along the yaxis as the leading coefficient. Positive => upwards, negative => downwards.