Question

question 2 of 10 find the solutions to the equation below. check all that apply. 9x^2 - 81 = 0 a. x = - 3 b. x = 9 c. x = 3 d. x = - 9 e. x = - 81 f. x = 1

Explanation:

Step1: Isolate the $x^2$ term.

Add 81 to both sides of the equation $9x^{2}-81 = 0$. We get $9x^{2}=81$. Then divide both sides by 9, so $x^{2}=\frac{81}{9}=9$.

Step2: Solve for $x$.

Take the square - root of both sides. Remember that if $x^{2}=a$ ($a\geq0$), then $x=\pm\sqrt{a}$. So $x = \pm\sqrt{9}=\pm3$.

Answer:

A. $x = - 3$
C. $x = 3$