Question

Fatore 9𝑎2 − 4𝑏2.

Answer 1

\[x^2-y^2=(x+y)(x-y)\]
put \(x=3a\) since \((3a)^2=9a^2\) and put \(y=2b\) for a similar reason

Answer 2

in english (math english) this is called "the difference of two squares"

Answer 3

let me know what you get and i will check it

Answer 4

3a2 - 2b2

Answer 5

ok i think i have confused you
lets start again

Answer 6

factor means write as a product, like \(33=3\times 11\) or
\[x^2+2x=x(x+2)\]
your job is to factor
\[9a^2-4b^2\] so your answer should look like
\[(\text{something})(\text{something else})\]

Answer 7

for the difference of two squares
\[x^2-y^2\] you factor as
\[x^2-y^2=(x+y)(x-y)\] the right side of the equal sign is the "factored form"

Answer 8

you have
\[9a^2-4b^2\] and this looks a lot like \(x^2-y^2\) where \(x=3a,y=2b\) so you factor it as
\[9a^2-4b^2=(3a+2b)(3a-2b)\] and that is the answer

Answer 9

i hope that made it somewhat more clear, if you have a question let me know

Answer 10

how i find xy know that 𝑥2 + 𝑦2 = 67 e (𝑥 + 𝑦)2 = 185.

Answer 11

?

Answer 12

i need find X and y

Answer 13

i think there might be some sort of typo here
you want \(xy\) and you know \((x+y)^2=185\) right?

Answer 14

oh i see, and you know \(x^2+y^2=67\) right?

Answer 15

go it
lets go slow

Answer 16

\[(x+y)^2=x^2+2xy+y^2\] or
\[(x+y)^2=x^2+y^2+2xy\]

Answer 17

you know \((x+y)^2=185\) and \(x^2+y^2=67\) so we substitute
\[\large \overbrace{185}^{(x+y)^2}=\overbrace{67}^{x^2+y^2}+2xy\]

Answer 18

then we can solve for \(xy\)
\[185=67+2xy\\
118=2xy\\
59=xy\]

Answer 19

Ok, thanks!

Answer 20

yw

Answer 21

Let A = {X and Z | -40 <x <10} and B is a subset of Z such that the largest integer that B belongs is 5 and x, then x belongs to B - 1 also belongs to B.

Answer 22

a) Determine B, A union B and A intersection B
b) Justify the statement: This is not contained at B

Answer 23

a) and b) about the last question. ''Let A={X....