Question

solve: $16x^{2}-81 = 0$
a $-\frac{4}{9}, \frac{4}{9}$
b $-\frac{81}{16}, \frac{81}{16}$
c $-\frac{16}{81}, \frac{16}{81}$
d $-\frac{9}{4}, \frac{9}{4}$

Explanation:

Step1: Isolate the $x^2$ term

$16x^2 = 81$

Step2: Solve for $x^2$

$x^2 = \frac{81}{16}$

Step3: Take square root of both sides

$x = \pm\sqrt{\frac{81}{16}} = \pm\frac{9}{4}$

Answer:

D. $-\frac{9}{4}, \frac{9}{4}$