Question

Factor the expression.

k2 – 9h2

Answer 1

bionmial \[(a+b)(a-b) = a^2 - b^2\]

Answer 2

I don't get it do we plug them in

Answer 3

formula is actually called difference of squares, and you can also have numbers
example:
\[(a+4b)(a-4b) = a^2 -4ab +4ab -16b^2\]

Answer 4

this uses FOIL, and -4ab +4ab cancel out

Answer 5

can you try the same with the one in the problem?
\[k^2 - 9 h^2\]

Answer 6

\[(a+4b)(a-4b) = a^2 -16b^2\]
similar:
\[(k+..)(k-..) = k^2 -9h^2\]

Answer 7

how do I do this again I am confused

Answer 8

The original equation looks like this
\[k^2 - 9 h^2\]

Answer 9

so it looks like a difference of squares

Answer 10

yes

Answer 11

the formula for factoring a difference of squares:
\[(a+b)(a-b) = a^2 - b^2\]

Answer 12

what do I plug in for a and b

Answer 13

k and h