I had a table of values.

X / Y
-3/ 2.5
-2/ 5
-1/ 6.5
0 / 7

It asks without graphing. Does it open upward or downward.
I got that in the quadratic equation. a= -0.5
And if a is smaller than 0. It opens downward
However. The text book says it opens upward. So I'm confused

2 answers

What was your quadratic equation ?

Make sure that all your points satisfy it, if even one of them does not work, your equation is wrong.

If they do, and a is negative, then it opens downwards. If your a is positive then it opens up
clearly it opens downward, since for equal increments of x, y is increasing, but more and more slowly. That means that soon it will turn around and start decreasing.