Bonjour pourriez vous m'aider avec cette équation du second degré? j'ai du mal à comprendre le concept. merci -9x² + 1 = 0

If a quadratic equation has solutions, the standard procedure will always work: given an equation like

The solutions (if any) are given by

In your case, you have

So the formula becomes

Anyway, this is quite a special case, because you're missing the linear term (since )

This means that you can solve equations like these more easily: rearrange the equation to make it look like . In your case, it becomes

Divide both sides by 9:

Now, you know that the square of a number equals 1/9. By definition, it means that this number is the square root of 1/9. Nevertheless, both the square root and its opposite are solutions of the equation, because the minus sign will cancel out when squaring.

So, in general, you have

which of course makes sense, if you're using real numbers, only if c/a>0.

In your case, this becomes

answer: a and b

step-by-step explanation:

x=30

step-by-step explanation: