Question

(3√2-9)(3√2+9)

Answer 1

do you know how to put the 3 into the √2?

Answer 2

hmm, im not sure on that

Answer 3

ok what's the square of 3?

Answer 4

1.73205

Answer 5

sorry, i meant 3 on the power of 2, aka 3x3

Answer 6

oh that would be 3

Answer 7

no, ok whats 3x3?

Answer 8

9

Answer 9

ok now multiply it into the √2
√2x9

Answer 10

12.7279?

Answer 11

ok, 2x9?

Answer 12

18

Answer 13

great! so now we have √18, you get it?

Answer 14

ohh okay , i see

Answer 15

ok so now where have:
(√18-9)(√18+9)
when you multiply a √ with another √, it doesn't really exist anymore...

Answer 16

so it would be (18-9)(18+9) ?

Answer 17

not yet. you have to open the brackets.

Answer 18

18-9 x 18+9 ?

Answer 19

you still have the brackets:
√18-9 x √18+9

Answer 20

√18x√18=?
-9x9=?

Answer 21

√18x√18= 18
-9x9= -81

Answer 22

good! so now 18-81=?

Answer 23

-63

Answer 24

yep! that's the answer

Answer 25

ahh i seee, thanks man!

Answer 26

anytime!

Answer 27

@Miracrown

Answer 28

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