Question

is the polynomial a difference of squares and if it is factor the polynomial. y^2-9

Answer 1

y^2 and 9 are both perfect squares.

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

Answer 2

ok... what next?

Answer 3

well the individual terms are both squares and the '-' means 'difference' so what do you think?

Answer 4

is it a difference of 2 squares?

Answer 5

(y+3)^2?

Answer 6

lets do the first part before we write the expression - is y^2 - 9 a difference of 2 squares?

Answer 7

yes

Answer 8

yes obviously it is

so take the square root of y^2 and 9 . The factors both have y and 3 in them . One has + and other a -.

Answer 9

ok

Answer 10

so one factor is (x + 3) - what is the other?

Answer 11

(y-3)

Answer 12

or x doesnt matter

Answer 13

yea

Answer 14

i should have written y

Answer 15

so the anwser is b

Answer 16

(y + 3)(y - 3)

if you expand this youll find that the 2 terms in y cancel out leaving only the y^2 and - 9

Answer 17

yes

Answer 18

thanks

Answer 19

have a great day!!!

Answer 20

what i wrte is the general identity

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

here a was y and b was 3

if you remember that you can do any complete the square problem

Answer 21

* fifference of 2 squares problem

just look out for the 2 perfect squares and the minus.