Question

Need reviewing help! Simplify: -3x^2y(x^2+2xy-5y^3)

Answer 1

@jim_thompson5910

Answer 2

this is -3x^2y(x^2+2xy-5y^3) right?

Answer 3

Yes

Answer 4

what is -3x^2y times x^2

Answer 5

-6x^2y?

Answer 6

the 2 in the x^2 does NOT multiply with the -3 to get -6

Answer 7

Just kidding

Answer 8

lol

Answer 9

so what is it instead?

Answer 10

wouldnt it still be the same?

Answer 11

if you're stuck, then here's a similar example

x^3 times x^5 = x^(3+5) = x^8

Answer 12

or would it be -2x^2

Answer 13

close

Answer 14

-3x^2?

Answer 15

x^2 times x^2 = ???

Answer 16

x^2?

Answer 17

no

Answer 18

x^2 itself means x squared

anything square is the number multiplied by itself

Answer 19

ex:

3^2 = 3*3

5^2 = 5*5

Answer 20

so you add them instead of multiply?

Answer 21

so...

5^2 times 5^2 = 5*5 times 5*5 = 5*5*5*5 = 5^4

shortcut:

5^2 times 5^2 = 5^(2+2) = 5^4

Answer 22

replace the '5' with 'x' since you can do it with any base number, meaning that

x^2 * x^2 = x^4

Answer 23

so that brings us back to

-3x^2y times x^2 = -3x^4y

Answer 24

see how I got this?

Answer 25

yeah, im sorry. i kept seeing it as 2y.

Answer 26

oh no sry, -3x^2y is really -3*x^2*y

Answer 27

i didn't feel like typing all those multiplication asterisks

Answer 28

im super confused now. lol

Answer 29

where at

Answer 30

let's go back to the beginning of what the problem wants


when you distribute this expression out

-3x^2y(x^2+2xy-5y^3)

you will get

( -3x^2y times x^2 ) + ( -3x^2y times 2xy ) + ( -3x^2y times -5y^3 )

basically you multiply the stuff on the outside, which is -3x^2y, by everything on the inside of the parenthesis and add

Answer 31

Yeah, i did that its the rest im trying to do. Having a brain fart or whatever. :p

Answer 32

ok tell me how far you got

Answer 33

oh you got up to this

( -3x^2y times x^2 ) + ( -3x^2y times 2xy ) + ( -3x^2y times -5y^3 )

??

if so, then you just need to multiply out each expression in the separate parenthesis groups

Answer 34

do you know what I mean?

Answer 35

Yeah

Answer 36

ok tell me what you get then

Answer 37

would the first one simp. be -2x^y

Answer 38

ugh

Answer 39

-3x^2y * x^2

-3(x^2*x^2)y

-3x^(2+2)y

-3x^4*y

so,

-3x^2y * x^2

turns into

-3x^4*y

Answer 40

notice how I grouped the terms with the same base

Answer 41

then multiplied it out to simplify

Answer 42

okay, that makes sense now. I just forgot how it worked.

Answer 43

that's ok

Answer 44

glad it's clicking now though

Answer 45

-3x^2y * 2xy turns into ????

Answer 46

in this one would it be -6x^2y^2 or -6x^3y^2?

Answer 47

the x^2 and the x multiply to x^3

Answer 48

aalright.

Answer 49

so it's the second one you got

Answer 50

-6x^3y^2 and the third 15x^2y^4

Answer 51

?

Answer 52

good, you got the 3rd one correct

Answer 53

so...

( -3x^2y times x^2 ) + ( -3x^2y times 2xy ) + ( -3x^2y times -5y^3 )

will turn into

( -3x^4y ) + (-6x^3y^2 ) + ( 15x^2y^4 )

and removing parenthesis gives

-3x^4y - 6x^3y^2 + 15x^2y^4

Answer 54

i got my answer as 6x^9y^5 is that right?

Answer 55

you cannot combine any terms because there are no like terms

Answer 56

besides, x^4 + x^3 is not x^7

Answer 57

oh, so i just leave it after i take away the parenthesis?

Answer 58

yeah you just leave something like x^4 + x^3 as it is...you cannot combine or simplify that at all

Answer 59

if you had x^3 + x^3, that's a different story

Answer 60

alrght(P:

Answer 61

but you don't