help

[frozen nimbus]

i literally just got out of school how did i forget this already
i already have a hunch but like just making sure
if the graph (quadratic) makes a n shape then a is positive right

[nocturne nimbus]

No its the other way around I think

[spark steppe]

It depends on the x intercepts as well but usually yes if it opens down the a value is positive

For example this parabola has a positive a value (vertex) since the vertex is 5,3

[steel aspen]

no if it open down the a value is negative

the vertex may be positive but the a value is what determines if the graph opens up or down