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X^2 - 9
find roots now

User Reiswindy
by
5.5k points

2 Answers

6 votes

There are 2 ways to do this.

1) First you need to factor x² - 9.

x² - 9 = (x + 3 )(x - 3)

So x = -3, 3.

2) Let x² - 9 = 0

So then add 9 to both sides and you'll get:

x² = 9

Square root both sides and you'll get:

x = ± 3 (Which is the same thing for -3, 3)

User Zoka
by
5.0k points
2 votes

Answer:

x = 3, -3

Explanation:

To find the roots, or solutions/zeros to this problem first you need to factor the quadratic equation.

In its factored form it looks like this:

(x + 3)(x - 3)

Make both of these factors equal to 0 to find the roots.

(x + 3) = 0

  • Subtract 3 from both sides... x = -3.

(x - 3) = 0

  • Add 3 to both sides... x = 3.

The roots of this quadratic equation are 3 and -3.

User Randal Cunanan
by
4.3k points