Question

Solve: 16x2 − 81 = 0.

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

Answer 1

hint:

16x^2 - 81 = A^2 - B^2

can you tell me what A and B are?

Answer 2

@pooja195 can help!

Answer 3

A and B are the numbers

Answer 4

right, but which numbers?

16x^2 - 81 = A^2 - B^2

what is A = ?

Answer 5

- 9 over 4?

Answer 6

... what?

Answer 7

so, if A^2 = 16x^2, what is A?

Answer 8

A is 16x^2

Answer 9

nope, not quite...

A^2 = 16x^2
A = ?

Answer 10

A is 16^2

Answer 11

nope, try one more time...

A^2 = 16x^2
A = square root of A^2 = ?

Answer 12

ITS 100

Answer 13

?

Answer 14

what is the square root of 16x^2?

Answer 15

Well 256 is what 16 times 16 equals but its Square root would just be 16 ._.

Answer 16

not quite

let's break it into two parts:

16 and x^2

what is the square root of 16?

Answer 17

4

Answer 18

right, now what's the square root of x^2?

Answer 19

Thanks for the help I already firguered out the answer its B

Answer 20

I mean C