Is this equation x^9-5x3+6= 0 in quadratic form

No, it's not. A quadratic form is something like

They won't necessarily come in this exact form, but the important part is that there must be a constant term, and the other two terms must be powers of the variable, and one must be the square of the other.

In this case, for example, is the square of

So, for example, an equation like

is in quadratic form, because there is a constant term (18), and is the square of . You can tell this because the exponents are one the double of the other.

So, in this case, you have which is the cube of , so this equation is not in quadratic form.

my guess would be b and d, but i didn’t actually get out the pen and paper. lol