Find the solutions to the equation below: x^2-9=0

Question

asked Mar 19, 2020 234k views

2 Answers

Graymatter · Answer 1 · 2020-03-23T17:36:03+0000

For this case we must solve the following equation of the second degree:

x ^ 2-9 = 0

We add 9 to both sides of the equation:

$x ^ 2-9 + 9 = + 9\\x ^ 2 = 9$

We apply square root on both sides of the equation:

$\sqrt {x ^ 2} = \sqrt {9}\\| x | = \sqrt {9}\\x = \pm \sqrt {9}\\x = \pm3$

Answer:

$x = \pm3$

The solutions are:

$x=3\ and\ x=-3$