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I'm supposed to factor a trinomial. I could use some help here, it's pretty tough.

18x5 + 15x4z - 75x3z2

Any ideas?

I'm supposed to factor a trinomial. I could use some help here, it's pretty tough.

18x5 + 15x4z - 75x3z2

Any ideas?

If I reading the problem correctly...
30x(4z+3)

It esay

factor out 3x3

other than that i forget how to do those

At least you lot can do these... I can't even do algebra without a calculator or help.

you have to clump all the terms together:

first, multiply the numbers:

18x5 + 15x4z - 75x3z2=90x+60xz-450xz

then factor

=x(30+60z-450z)=30x(1+2z-15z)=30x(-13z+1)

Got it wrong the first time, sry.

I'm supposed to get it in the format of (something)(something).


Fuck, I edited your post instead of quoting, sorry!

i did that crap last year, teacher right out said it wasnt important and we would use it, but we had to learn it

I'm supposed to factor a trinomial. I could use some help here, it's pretty tough.

18x5 + 15x4z - 75x3z2

Any ideas?

OOOhhh, I get to have this sort of fun at school too!

18x5 + 15x4z - 75x3z2 = 90x+60xz-450x

= x(30+60z-450z) = x(30 - 390z) = 30x(1 - 13z)

let's verify

let x=1 and z=1

(18)(1)(5) + (15)(1)(4)(1) - (75)(1)(3)(1)(2) = (30)(1)(1 - 13) ?

90 + 60 - 450 =/= -360

hmmmm...

Am I misreading it?

I'm supposed to get it in the format of (something)(something).
Do these somethings have to be sums or differences?

Are there any specific numbers x and z can be or a can they be any number?

I'm supposed to factor a trinomial. I could use some help here, it's pretty tough.

18x5 + 15x4z - 75x3z2

Any ideas?

First factor out 3x^3 this leaves 3x^3(6x^2 + 5xz - 25z^2).
Then it becomes 3x^3(3x - 5z)(2x + 5z)

Out of curiosity, what year of math is this?

Perhaps I mistyped it. It's 18x^5 + 15x^4z - 75x^3z^2. Note the squares, cubes, etc.

I'm supposed to get it in the format of (something)(something).





Quadratics suck x_X

There's a formula you need to get the reverse... I should look it up.

Um, southern industrial, if you're going to do something like divide out or multiply out you better be talking about an EQUATION, what we have here is an expression (difference is an = sign)

Anywho, Math wiz (and teacher) to the rescue!

18x^5 + 15x^4z - 75x^3z^2 (btw, ^ is the standard formatting for powers)

3x^3(6x^2 +5xz-25z^2) is one thing you can factor out.

From there it looks like we can...
3x^3(2x + 5z)(3x - 5z)

so that would be your factoring out.

What level you at?

18x^5 + 15x^4z - 75x^3z^2

Ok...

Hang on, is that last one 75x to the power of 3z squared? That's confusing...

Urg. Ok, now is the time to admit that GCSE maths, despite being in the top set, is not going to get me through this problem.

I'm supposed to factor a trinomial. I could use some help here, it's pretty tough.

18x5 + 15x4z - 75x3z2

Any ideas?
Does x mean multipiled by here or is it a variable?

If its a variable, then what does 18x5 mean? 18x^5? in which case, does 15x4z =15x^4z?

I don't mean to hijack the thread, but I feel this can be answered quickly and doesn't deserve the formation of a new thread. It's been a while since I've had a math class, so can someone please remind me how to get a radical out of the denominator?
(I have [3]/[the square root of 3])

Oh wait...
Multiply by [square root of 3]/[square root of 3] (which is the same as 1/1)
That gives... [3 square roots of 3]/[3]? Is this right? Shouldn't that cancel out to [square root of 3]

If its a variable, then what does 18x5 mean? 18x^5? in which case, does 15x4z =15x^4z?

Yes, 18x^5 and 15x^4z

Yes, 18x^5 and 15x^4z
(15x^4)z or 15x^(4z)

Probably the first one. Algebra II?

Yes, 18x^5 and 15x^4z

Ugh. Draw it out in Paint using normal handwriting then upload :headbang:

(15x^4)z or 15x^(4z)

(15x^4)z

I'll offer to help only after you admit that your political views are horribly wrong.

I'll offer to help only after you admit that your political views are horribly wrong.
LOL

Ok time for a 94% Math student to take over...

18x^5 + 15x^4 z - 75x^3 z^2

If I'm reading that right.

First, factor something out.

3x^3 (6x^2 + 5xz + 25 * z^2)

And shit... It's been a year since that course..... I forget what to do next... :(


When typing equations out, to the person who asked what "x" was, you should always use * for multiplication because x is a variable.

you think i'm gonna do your math homework for ya?
fat chance, fatso.

cmon now, i got it right here....

(9x^3 - 15x^2 *z)(2x^2 + 5zx)

Letila: I'm guessing it's
18(x^5)+15(x^4)(z)-75(x^3)(z^2)

Now watch this.....

18(x^5)+15(x^4)(z)-75(x^3)(z^2)
(6)(3)(x^3)(x^2)+(5)(3)(x^3)(x)(z)-(3)(25)(x^3)(z^2)
3(x^3)[(6(x^2)+5(x)(z)-25(z^2)]
3(x^3)[(2x+5z)(3x-5z)]
(3x^3)(2x+5z)(3x-5z)


Opal Isle: You want to simplify (3/sqrt(3)). Done. (Sorry, but this is going to be kind of difficult to follow with one-line math.)

3/(sqrt(3))
(3/sqrt(3))((sqrt(3))/(sqrt(3)))
(3 sqrt(3))/((sqrt(3))*(sqrt(3)))
(3 sqrt(3))/3
sqrt(3)
So yes, it does cancel out to the square root of 3.


And don't worry, I am in AP Calculus AB. (In fact, I spent some time yesterday explaining to a friend why (lim x --> 1/2)(x sec (pi*x)) does not exist.) So I hope you think I'm qualified.

Oh, and if you want to check your answer online (come on, no cheating), I recommend www.quickmath.com (http://www.quickmath.com).

Certainly hope that helped...

(9x^3 - 15x^2 *z)(2x^2 + 5zx)

You'd have to factor out 3x^2 from the first term and x out of the second term to completely factorize the polynomial, unless of course you only needed two terms.

That's what Letila said...

If you meant:
(18 * x^5) + (15 * x^4 * z) - (75 * x^3 * z^2)
or:
18x^5 + 15x^4z - 75x^3z^2 (as it might look more like on paper)

Then I think the answer is:
(3 * x^3) * [(6 * x^2) + (5 * x) - (25 * z^2)]

I used the extra "*" and "()" to hopefully make it easier to read on the computer. Written down on paper, is might look more like:
3x^3(6x^2 + 5x - 25z^2)

If that is indeed the answer, then it is a monomial times a trinomial, however useful that is.

Thank you.

I'm supposed to factor a trinomial. I could use some help here, it's pretty tough.

18x5 + 15x4z - 75x3z2

Any ideas?

It can be taken one step further.

18x^5 + 15x^4z - 75x^3z^2
-------------------------------
3x^3 (6x^2 + 5xz - 25z^2)
-------------------------------
The answer is:
(3x^3)(3x-5z)(2x+5z)

Squornshelous is correct, I accidentally dropped a "z" term. Sorry 'bout that. Haven't been thinking as clearly and carefully as I should because of summer vacation.

The answer is in fact:
(3x^3)(3x-5z)(2x+5z)
as Squornshelous said.