Gone back to college recently and I am struggling somewhat with math (haven't done math in 10+ years). I just got done with Intermediate Algebra and now I have moved on to College Algebra. I am taking 100% online courses since I work full-time and have a family. Because of that, much of the stuff I am "taught" is self learned. I will keep this thread refreshed throughout the semester and post problems that confuse me with the hopes of a more thorough breakdown from math geniuses like yourselves.

First problem area: Graphing

I am decent at BASIC graphing (plotting points, finding the slope, etc..), but I have gotten into some more heavier stuff now. I have to find the distance between points right now. Some of it is easy, but some is challenging. One thing I am caught up on right now is fractions. I've always been horrible at fractions.

Here is the problem:

Find the midpoint of the segment with the given endpoints.

I know the formula, I just don't know how to make it work with fractions.

(3/4 , -4/5) and (-1/8 , 3/4)

If someone can breakdown the steps to this problem that would be great!

If you already know the formula :
midpoint's coordinates are the average of both endpoints coordinates.

With your fractions :

( 3/4 + -1/8 ) / 2

and

( -4/5 + 3/4 ) / 2

X-coordinate = (6/8 - 1/8) / 2 = (5/8) / 2 = 5/16
Y-coordinate = ( -16/20 + 15/20 ) / 2 = (-1/20) / 2 = -1/40

the thing is, you can do the x and y's separately
(x1,y1) (x2,y2)

find mid point between the x's first by adding them and dividing by 2
for your fractions, it's intended for you to get them to a similar format.
you got 3/4 and -1/8 fr your c coordinates

multiply 3/4 by 2/2 to get 6/8
so you have 6/8 + -1/8 which is 5/8
divide by 2 to get 5/16. that's the mid point for the x

repeat for the y coordinates

ah, GCD. I was finding the GCD like I was supposed to but I cancelled out the denominator afterwards and left just the numerator as a whole number. So I was partly there I guess, lol. Awesome, thanks for the help!

Next problem stuck on



In my mind I'm wanting to do:

7x-4 * 3-5x

and

3-5x * 7x-4

But that isn't right. Help?

This post was edited by Dune1 on Sep 25 2014 06:52pm

Nope.

For these, you have to plug one function into the x value for the other function

For example

(f o g)(x)

You will be plugging the fuction g(x) into the X value for f(x)

7(3-5x) - 4

21 - 35x - 4

-35x + 17

Ah. Awesome, got it!

I have my first exam tomorrow so I'm cramming the study time in. I'm struggling with some VERY basic math right now and cannot seem to get it right no matter what I do. I suck at fractions and whenever I see them my heart starts to race.

I am struggling with multiplying, adding, and subtracting whole numbers and fractions.

Example:

5/7(-8) and -4/9(-3)

and

3/8 - 4

and

2/5 + 6

These are just some examples I conjured up. I would like a detailed break-down on how to solve these type of problems.

Thanks!

what's intended for you,

You need to get everything to like bases

So, you want every term to have the same bottom number. That way you can combine fractions.


2/5 + 6 : get a denominator of 5 for the 6.


So, multiply 6 by 5/5 to get 30/5 .
if you needed a base of 7, multiply by 7/7

since you have like bases, you can combine the fractions and add or subtract the top number


2/5 +30/5 = 32/5

That's what I thought I've been doing but I keep getting the wrong answer.


Here's the actual problem:

m = 7/8, (7,-8)

My answer: y = 7/8x - 120/8

Correct answer: y = 7/8x - 113/8

This post was edited by Dune1 on Oct 2 2014 04:15pm