Intermediate Algebra help

meandragonbrett · Jan 30, 2003

My honors calculus teacher taught us a really easy way to do them....but I can't explain it over the net. Sorry I can't help you. Search the net some...you might be able to find it explained a different way and it might click.

Good Luck!

Brett

adrienurse, LPN · Jan 31, 2003

I'm having algebra problems too. It's been 10 years since I've done this sh*t and I can't remember how to isolate variables or the order of operations. Anybody know any good tutorial sites. Anyone want to tutor me? :)

SirJohnny · Jan 31, 2003

SOLUTION: "SYSTEM OF EQUATIONS" PROBLEM

STEP 1: SETUP THE EQUATIONS:

(0.15)X + (0.45)Y = 300(0.35) [TOP EQUATION]

X + Y = 300 [bOT EQUATION]

STEP 2: SIMPLIFY TOP EQUATION:

(0.15)X + (0.45)Y = 105 [TOP EQUATION]

DO NOTHING WITH BOT EQUATION: X + Y = 300 [bOT EQUATION]

STEP 3: DIVIDE TOP EQUATION BY (0.15)

X + 3Y = 700 [TOP EQUATION]

DO NOTHING WITH BOT EQUATION: X + Y = 300 [bOT EQUATION]

STEP 4: MULTIPLE TOP EQUATION BY (-1)

-X + -3Y = -700 [TOP EQUATION]

DO NOTHING WITH BOT EQUATION: X + Y = 300 [bOT EQUATION]

STEP 5: ADD TOP AND BOT EQUATION TOGETHER:

-2Y = -400

STEP 6: DIVIDE BOTH SIDES BY (-2)

Y = 200

STEP 7: SUBSTITUTE "Y=200" INTO EITHER THE BOT OR TOP EQUATION. DOES NOT MATTER WHICH EQUATION YOU USE. I SHOW BOTH JUST AS AN EXERCISE.

[TOP EQUATION]

(0.15)X + (0.45)200 = 300(0.35)

(0.15)X + 90 = 105

(0.15)X = 105 - 90

(0.15)X = 15

X = 100

[bOT EQUATION]

X + 200 = 300

X = 300 - 200

X = 100

STEP 8: PROVE BY LETTING X = 100 & Y = 200 AND SUBSTITUTING INTO EITHER TOP OR BOT EQUATION.

[TOP EQUATION]

(0.15)100 + (0.45)200 = 300(0.35)

15 + 90 = 105

105 = 105 ** IMPORTANT THAT BOTH SIDES ARE SAME ***

STEP 9: WRITEUP YOUR ANSWER:

YOU NEED 100ml of solution X which is a 15% solution.

YOU NEED 200ml of solution Y which is a 45% solution.

ADD THESE TOGETHER AND YOU GET 300ml of solution Z which is a 35% solution.

===============

John Coxey

([email protected])

MS-COMPUTER SCIENCE ---> LOOKING TO BECOME RN SOMEDAY I HOPE!!!!

SirJohnny · Jan 31, 2003

Sorry - could not get equations to line up.

Cut and paste into NotePad. Use CourierNew font so text

will line up. Can't do with default TimesRoman.

Then manually line up the TOP & BOT equations for each

step and things will be much clearer.

----------------

Whenever you get a word problem. Trick is to try to see how

to make it fit into the general equations for the section you

are working on.

If you are doing regular math problems for that section, then

try to make the word problems fit into the regular math problems.

A bear, I know.

I took Calculus 5 times - but ended up with a BS-Applied Mathematics and finally an MS-Computer Science.

Am working in computer industry - but want to pursue career in nursing.

John Coxey

([email protected])

MishlB · Jan 31, 2003

http://mathforum.org/dr.math/

Works every time!!!!!!!!!

Mkue · Jan 31, 2003

wow, where were you guys when I took algebra??? lol.. great info.

Sally_ICURN · Jan 31, 2003

John you boggle my mind!! My daughter is currently in a doctoral program at UC San Deigo. Her area is math. She teaches undergrad as well as completing her own studies--she's only 24! I was chatting with her online just now and was going to ask her the question. I have a ton of respect for people who can explain math...period! Great minds!!

~Sally :cool:

melissa24 · Jan 31, 2003

John Coxey...

You rock! :cool:

passing thru · Jan 31, 2003

IMPRESSIVE ! JOHN !

Home Health Columnist / Guide · Jan 31, 2003

John, can you tutor me in statistics in exchange for nursing knowledge???

adrienurse, LPN · Jan 31, 2003

Okay people. Here's one that I'm stuck on.

formula is:

z=(a-b)/c

z=-1.5

a=75

c=10

What is b?

Making my head hurt just thinking about it.