Math Help

Posts Tagged ‘Math Help’

Question: PLease Help on 3 math problems with multiplying fractions?

Directions: Perform the multiplication and express the product its simplest form

11) 4x + 8y / 6x + 18y (times) 5x + 15y / x^2 – 4y^2

13) 4 – 2x / 6x + 30 (times) x^2 – 25 / x^2 – 7x + 10

14) 4y^3 / 8 – 2y – y^2 (times) 3y + 12 / 6y

Answer: HI,

11) 4x + 8y / 6x + 18y (times) 5x + 15y / x^2 – 4y^2

4x + 8y……5x + 15y
———–.X.———— =
6x+18y…….x² – 4y²

4(x + 2y)……5(x +3y)
————-.X.—————– =
6(x+3y)…….(x – 2y)(x+2y)

2……..5
—.X.———– =
3…….(x – 2y)

10
———— <== ANSWER
3(x - 2y)

13) 4 - 2x / 6x + 30 (times) x^2 - 25 / x^2 - 7x + 10

4 - 2x.......x² - 25
--------.X.------------- =
6x+30.....x²-7x+10

2(2 - x).....(x - 5)(x + 5)
----------.X.---------------- =
6(x+5)..... (x - 2)(x - 5)

Cancel out the x+5 and x - 5 factors.

2(2 - x).........1
----------.X.-------- =
6.............. (x - 2)

Cancel out the 2 - x and x - 2 factors. They are opposite factors and leave a "-1" in place of the (2 - x) factor.

2(-1)
------- = -⅓ <== ANSWER
6

14) 4y^3 / 8 - 2y - y^2 (times) 3y + 12 / 6y

..4y³...............3y+12
-------------.X.---------- =
8 - 2y - y²..........6y

..4y³...................3(y+4)
-----------------.X.---------- =
(4 + y)(2 - y)..........6y

Reduce 4y² and 6y. Cancel the y + 4 factor.

..2y²
------- <== ANSWER
2 - y

I hope those help!!

Multiplying Fractions – YourTeacher.com – Algebra Help

Question: Help with easy math factoring?

my answer is similar to the one in the back of the book, but it’s not the same. I just want to see EXACTLY what i did wrong.

so if anyone could show me the steps to completing this question i would be thankful.

Factor:

2m^2+10m+10n-2n^2

Thank you in advance

Answer: 2m^2 + 10m + 10n – 2n^2

2m (m + 5) + 2n (5 – n)

2 [ m (m + 5) + n (5 - n) ]

I’m not sure how far you have to go.

Algebra – Factoring Part 1 Polynomials Intuitive Math Help

Question: Help With Math/calculus?

I am in calculus 151. I have worked a problem down to: (7-8x^2)/(x^3). I don’t know what to do from here. I feel as if it is easy, but I’m having some trouble.
I know I need to simplify and solve for x, but I’m not sure where to go from here.
That’s what I started with, and I got it to this. I go to Ohio State, and this is the first calculus for me. I just need to solve for x to find the domain.
Wow, I can’t believe I didn’t see that, I’m not thinking tonight, waaaay too many of these problems.. thanks a lot man

Answer: You sound like you might go to Rutgers, since that’s the name of Calculus 1 for engineers at Rutgers.

This is not really simplifying but you can write this as:

(7 – 8x^2)/(x^3) = (7/x^3) – (8x^2)/(x^3) = (7/x^3) – (8/x).

EDIT: If this is your function then the domain is trivial. It would just be all real numbers except 0. i.e.

(-infinity, 0)U(0, infinity)

Calculus – Derivative Intro Derivatives Intuitive Math Help What Is The Difference Quotient