Question

: i need plato help ! What is (5x)(14x3)?

Answer 1

Ready to work this together?

Answer 2

yess :) im ready. its for a semester test . so i need help plss ! i would appreciate iht(:

Answer 3

Sure thing. Just want to double check: 5x times 14x to the 3rd, right?

Answer 4

Is that the correct interpretation of the question?

Answer 5

don't bother, some idiot already just gave the answer, so she's moved on..

Answer 6

Haha oh well. Unfortunate, as these folks will often be the ones who suffer on the tests. :/

Answer 7

except that I think a lot of them do tests online and just get help here on their tests even.

Answer 8

such is the tragic state of our education system

Answer 9

i need yur help. uber were did you go?

Answer 10

Right here. What's up?

Answer 11

He was helping.. you were the one who left.

Answer 12

sorrry ! i thought he had read my other post cuss i update all in different post

Answer 13

Simplify the expression (4x − 3)(x + 5).this one is next.(:

Answer 14

Ok. Do you know about "FOIL"?

Answer 15

yess, kinda. buht can you give me a brief summary bout iht.

Answer 16

Sure. FOIL = "first outer inner last" This means you multiply each of the numbers in the brackets as given. So first, what is the first number in each parenthesis (including the x)?

Answer 17

Very brief summary:

\[(a+b)(c+d) = (a\times c) + (a\times d) + (b\times c) + (b \times d)\]

Answer 18

Nice! I like that.

Answer 19

I never do it that way myself..

I always just distribute.

Answer 20

BTW, Polpak: I got bored enough to do 'normal' multiplication on polynomials, and found out it still works. I've always wondered why they make us do FOIL instead of, say,

3x + 7
* 2x - 4
-------

^^^^^^ Unrelated, btw to your question jacyy, so ignore it :P ^^^^^^^

Answer 21

ha ok. buht the thing i dont get ios if we are solving for ex or whatt?

Answer 22

lol.. I always just do:

(a + b)(c+d)
= a(c+d) + b(c+d)
Or (depending on what looks nicer)

=c(a+b) + d(a+b)

Answer 23

We aren't solving for x, just expanding out the expression.

Answer 24

by carrying out the multiplication.

Answer 25

Nope. We're just making a nicer looking equation. Getting rid of the parentheses basically.

Answer 26

Like going from 4+4+4+4+4+4 to (4)*(6). Kinda.

Answer 27

Alright, so first we need to make sure you understand FOIL. Do you know what it's trying to say?

Answer 28

ohhh okaay, thanks. is the answer 4x^2+17x-5

Answer 29

yess ii do understand foil:)

Answer 30

Almost..

Answer 31

Honestly, I don't think so. But let me double check.
4x − 3)(x + 5)

Answer 32

Double check your math on the 'L'ast term.

Answer 33

VERYYYYYYYY close, as polpak said. :D

Answer 34

ARgghhh... is anyone else getting like 4 second lag between posts?

Answer 35

okay will iht be - than + add the end

Answer 36

no, look at your last terms:

-3 and 5

What is -3*5 ?

Answer 37

yeah i don't like teaching people about foil unless i thought them why you can do it
(a+b)(c+d)=a(c+d)+b(c+d) or (a+b)c+(a+b)d

Answer 38

yes, silly algebra teachers think that learning 'foil' is easier than distributing when you already went to the trouble of learning to distribute before foil.

Answer 39

you can'd do foil on (a+b+c)(d+e+f)
you have to distribute
so there is almost no point in learning foil sense it is a weak method

Answer 40

-15

Answer 41

(a+b)(c+d) foil only works on things like above

Answer 42

Right. So 4x^2 + 17x -15

Answer 43

Factor completely: 3x2 − 17x − 28 i got the other one thanks

Answer 44

@mini: even then, I like doing classic multiplication as opposed to distributing. So much easier! :D
I mean, I know it's still distributing, but it's so much more easier.

Answer 45

So factoring is just the opposite.

Answer 46

3x2 − 17x − 28
For this one, using the quadratic equation is the easiest way. Though the other folks can probably teach you the "real" way to do it.

Answer 47

We are looking for some a and b such that:

(3x + a)(x+b) = 3x^2 - 17x - 28

Answer 48

Sadly, I am in Cal 2 and have yet to learn how to factor complex polynomials. Heh.

Answer 49

brb

Answer 50

So using our 'foil' method:

\[3x^2 + (3b + a)x + ab =3x^2 - 17x - 28\]

Answer 51

Hmm... let's see if I can handle that...

Answer 52

3x^2 + (3b+a)x + (4,7 or 14,2)

Answer 53

plus or minus, of course.

Answer 54

you can'd do foil on (a+b+c)(d+e+f)
you have to distribute
so there is almost no point in learning foil sense it is a weak method

Answer 55

Ax^2+Bx+C
find two factors of A*C that multiply to be A*C and add up to be B.

A=3, B=-17, C=-28

A*C=3(-28)=12(-7)=6(-14)=2(-42)=4(-21)

B=-17=-21+4

so replace middle term with Bx=-17x with -21x+4x

so we have 3x^2-17x-28

3x^2-21x+4x-28


then factor by grouping

3x(x-7)+4(x-7)

(x-7)(3x+4)

Answer 56

Oh snap. Is it 3x^2 + x(3*7-4) + 7*-4?

Answer 57

Oh sorry, missed your post. And also realized I got positive 17. Bleh.

Answer 58

sorry i just came back

Answer 59

Question: 13 of 40: Factor completely: 3x2 − 17x − 28Select one of the options below as your answer: A. (3x + 4)(x + 7) B. (3x + 4)(x − 7) C. 3x2 − 17x − 28 D. (3x2 + 4)(x − 7) thats the question and answer s

Answer 60

That means:

3b+a = -17
and
a*b = -28

Answer 61

and I see the others have already done it.

Answer 62

you know multiplication is communative right?
a*b=b*a
3*2=2*3

Answer 63

commutative*

Answer 64

im confused:/

Answer 65

which part confuses you?