## Search found 11 matches

Wed Sep 19, 2012 8:31 pm
Forum: Intermediate Algebra
Topic: Solving a system of two eqn's.
Replies: 3
Views: 1942

### Re: Solving a system of two eqn's.

Don't get too caught on up on the fact that the equations might look a little different than what you are used to. The same ideas and concepts work just like always. (13/x) - (2/y) = - 0.3 (14.6/x) - (0.4/y) = 0.04 When your variables are the denominator of fractions, it's usually going to be easier...
Mon Sep 17, 2012 2:21 pm
Forum: Beginning Algebra
Topic: in 2008, 565650 Americans died of (all form of) cancer.
Replies: 2
Views: 3729

### Re: in 2008, 565650 Americans died of (all form of) cancer.

This is really just a ratio question.

"in 2008, 565650 Americans died of (all form of) cancer. Assuming a population of 305 millions, what was the mortality rate in units of deaths per 100000 people?"

You could set this up as 565650/305000000 = x / 100000 and go from there.
Sun Sep 16, 2012 2:49 pm
Forum: Pre-Algebra
Topic: Need help solving 9x^3 - 42x^2 - 24x
Replies: 6
Views: 6990

### Re: Need help solving 9x^3 - 42x^2 - 24x

When factoring 3x² - 14x + 8, you'll need to find two numbers that multiply to give you ac while adding to give you b. In this case, ac = 3(8) = 24 and b = -14. We'll want to look at negative factors of 24 since we need them to add up to a negative number: -1 -24, sum = -25 so that's not it -2 -12, ...
Sun Sep 16, 2012 2:42 pm
Forum: Beginning Algebra
Topic: Factor x(2) + 4x - 12, how?
Replies: 7
Views: 17066

### Re: Factor x(2) + 4x - 12, how?

It's not as difficult as it might sound to list out all of the possible factors to see what they add up to. Suppose we have: 8x² + 24x + 10 So you're looking for two numbers that will multiply to give you 80 and that add to give you 24. Let's look at the factors of 80 by just starting at 1 and seein...
Sun Sep 16, 2012 4:07 am
Forum: Pre-Algebra
Topic: can't remember how to solve (x+5)-2(4x-1)=0
Replies: 2
Views: 7821

### Re: can't remember how to solve (x+5)-2(4x-1)=0

Start off by simplifying everything that you can. Maybe try multiplying out the -2(4x-1) part? :) (x + 5) - 2(4x - 1) = 0 x + 5 - 8x + 2 = 0 Don't forget that you have to multiply out by -2 instead of just 2, so you'll get -8x + 2 instead of 8x - 2. From there, you can simplify some more and try to ...
Sat Sep 15, 2012 4:12 pm
Forum: Pre-Algebra
Topic: How to solve order of operations w/missing number
Replies: 3
Views: 7739

### Re: How to solve order of operations w/missing number

With 76-?/2=41, you would write the equation out as 76 - x/2 = 41 and solve for x. Note that there are no parentheses around the 76 - x part, so the first thing you would be doing in the problem is dividing x by 2. I would start out by subtracting 76 from both sides: 76 - x/2 = 41 76 - x/2 - 76 = 41...
Fri Sep 14, 2012 8:36 pm
Forum: Beginning Algebra
Topic: Factor x(2) + 4x - 12, how?
Replies: 7
Views: 17066

### Re: Factor x(2) + 4x - 12, how?

I prefer the "magic number" way of factoring trinomials since the people I've worked with have seemed to understood it better that way. If your trinomial is in the form of ax² + bx + c, then you find two numbers that multiply to give you the product ac and that add to give you b. With your expressio...
Wed Jun 01, 2011 11:41 pm
Forum: Intermediate Algebra
Topic: Simplifying Complex Fraction
Replies: 8
Views: 4430

### Re: Simplifying Complex Fraction

(\frac{2(3x-1)}{x-1})(\frac{(1-x)(x-1)}{3x-1}) Can I cancel out both (x-1)'s and (3x-1)'s at this point? Would 2(1-x) be the wrong answer? You're right. It should go: (\frac{2(3x-1)}{x-1})(\frac{(1-x)(x-1)}{3x-1}) (\frac{2}{x-1})(\frac{(1-x)(x-1)}{1}) Canceled out 3x - 1. (\frac{2}{1})(\frac{(1-x)(...
Wed Jun 01, 2011 11:37 pm
Forum: Intermediate Algebra
Topic: Simplifying expression: x - (x - 1) / [x / (x + 1)]
Replies: 2
Views: 4028

### Re: Simplifying expression: x - (x - 1) / [x / (x + 1)]

x - \frac{x-1}{\frac{x}{x+1}} The book gives an answer of \frac{1}{x} . This is probably very simple problem but I really don't understand how to workout a problem like that. I would appreciate if anyone would like to show the steps involved getting to that answer and maybe point to a related lesso...
Wed May 25, 2011 12:17 pm
Forum: Intermediate Algebra
Topic: Simplifying Complex Fraction
Replies: 8
Views: 4430

### Re: Simplifying Complex Fraction

Question: \frac{5+\frac{x+3}{x-1}}{\frac{3x-1}{1-x^2}} I'm guessing I have to get rid of the fractions by multiplying by the LCD, but I feel like I am missing a step in even getting that. I would be inclined to start like this. Keeping in mind that \frac{\frac{a}{b}}{\frac{c}{d}} = (\frac{a}{b})(\f...