What are 3 quadratic equations that could equal ± 9?

Answer 1

Hi Katherine!

Going by the words in this question.

1. We need an equation, so certainly "=" is the most important ingredient.

2.Since the question says that the equation must equal to ±9, we know that ------- = ±9

3.The word "quadratic" in the question suggests that the other side of the equation must have a variable to the second power. In other words, the degree of the equation is 2.

So, the equation could be x² = ±9. This also means x² = 9 or x² = -9.

What are your thoughts about x² = -9 ? Is that possible or not? Why?

So far you have at least one out of the 3 quadratic equations that the question asks for.

Suppose your question is worded as What 3 quadratic equations could have the solution ±9, that is totally different!!

A second degree equation has, at the most 2 solutions.

In this situation, one quadratic equation could be y²= 81.

You can solve for y using the Square Root Property or by simply asking yourself the question , "what number times itself will give me 81?"