Question

Solve: 16x2 − 81 = 0.
I worked it and got 12.728... Please help.

Answer 1

Is it 16x^2?

Answer 2

First thing I did was write down a b and c
a: 16
b: 0
c: -81
Yes. 16x^2

Answer 3

Do you need to graph it?

Answer 4

No solve it using quadratic equations.

Answer 5

OK so do you know what the quadratic formula is, correct?

Answer 6

Yes. Is my a,b, and c correct?

Answer 7

I believe so

a = 16
b = 0
c = -81

Answer 8

Do you have any choices? Just in case

Answer 9

x = -0 +- _/0^2 - 4(16)(-81)/2(16)

Answer 10

x = 4, 9
x = −4, −9
x = 9 over 4, x = −9 over 4
x = 81 over 16, x = −81 over 16

I wanted to learn it without choices thou :/

Answer 11

Understandable, Give me a second to solve it myself

Answer 12

This is our quadratic formula, and we need to plug everything in, so