Question

factor:
see below:

Answer 1

\[81z ^{2}-4k ^{2}\]

Answer 2

hint:

a^2 - b^2 = (a-b)(a+b)

Answer 3

please show steps because I am confused.
Thank you

Answer 4

9^2?

Answer 5

9^2-2^2

Answer 6

81z ^2 = (9z)^2

and

4k^2 = (2k)^2

Answer 7

so you really have

(9z)^2 - (2k)^2

now use the rule given above

Answer 8

It is a difference of squares
a^2 = 81
b^2 = 4

(aZ+bK)(aZ-bK)

Answer 9

ok thanks a lot

Answer 10

how do you know if positive or negative in answer?

Answer 11

and which is positive or negative

Answer 12

if the problem is negative. means every factored answer has a one negative and one positive?

Answer 13

answer:
\[(9z ^{2}-2k ^{2})(9z ^{2}+2k ^{2})\]

Answer 14

not sure what you mean, but you'll have a positive portion and a negative portion

Answer 15

no it should be

(9z - 2k)(9z + 2k)

Answer 16

using the difference of squares rule

Answer 17

ok I think I got it now

Answer 18

ok great