solve: 16x² - 81 = 0\na -4/9, 4/9\nb -81/16, 81/16\nc -16/81, 16/81\nd -9/4, 9/4

Answer:

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

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