Science & Mathematics - 18 January 2007

what is the best method to solve the system of equation??

2007-01-18 13:29:21 · 5 answers · asked by gayle325 1 in Mathematics

A. 40.6
B. 24.3
C. 57.3
D. 72.8

2007-01-18 13:28:05 · 1 answers · asked by Anonymous in Chemistry

Which of the following is a one-to-one function?

a. {(-4,-9), (-2,-8), (-4,5), (-8,-20}

b. {(-4,-9), (-2,-8), (1,1), (-2,9)}

c. {(-4,-9), (-2,-8), (1,5), (-5,-9)}

d. {(-4,-9), (-2,1), (1,-2), (-5,-5)}

2. Which of the following is true of y=f(x)= ab salute value of (x) -4

a. f is a function.

b. There is a horizontal line that crosses the graph of y=f(x) more than once.

c. f is one-to-one.

d. f has an inverse.

e. a and b

f. b and c

2007-01-18 13:27:31 · 5 answers · asked by dallin.harmon 1 in Mathematics

2007-01-18 13:26:50 · 8 answers · asked by BETH H 1 in Mathematics

the density of an unknown substance is 312 kilograms per cubic meter. (a) what is the mass of 2.43 cubic meter of the substance? (b) how much does this substance weigh?

2007-01-18 13:26:00 · 2 answers · asked by argentina_mandy20 1 in Physics

A. 4.2 mol of carbon
B. 8.34 x 10 to the 24 power atoms of lead
C. 9500 formula units of calcium carbonate (CaCo3)
D. 12.6 g aluminum nitrate (al2(no3)3)

2007-01-18 13:24:48 · 2 answers · asked by Anonymous in Chemistry

2007-01-18 13:20:41 · 3 answers · asked by ±±±φ±±± schön 1 in Other - Science

moving a force of 512 newtons through a distance of 25.0 meters requires how many joules of energy? if johnathan did this 10 times, how many joules of energy did he expend? one food calorie = 4186 joules. how many food calories of energy did he use?

2007-01-18 13:19:35 · 1 answers · asked by argentina_mandy20 1 in Physics

Im currently in College precal and I just started today well anyways I pretty much know how to do ...... Factoring,extraction of roots, and quadratic formula. Im just practicing the "completing the square method" to better myself but for some reason I dont get the answer the same in the textbook.

The problem is:
2r^2+10r+11=0

Well this is what ive done so far....
r^2+5r+25/4= -22/4+25/4
(r+10/4)^2= 3/4
but for some reason i end up with...
r= -5/2 +or- Square root of 3/4 as my result

but my pre cal book has it as... r= (-5 +or- square root of 3)/2

What am I doing wrong? Am I not simplifying? Well after my end result I dont know what to do.

Thank you for everyones time.

2007-01-18 13:18:39 · 2 answers · asked by Anonymous in Mathematics

jim is practicing kangaroo handball, and he throws a 0.15 kg ball so that it hits a wall with a velocity of 18i + 3.2j m/s. since the wall is vertical, it changes only the ball's horizontal velocity. it exerts a force of -88.0i newtons on the ball for 0.060 secs. find the ball's intial and final momentum.

2007-01-18 13:16:55 · 1 answers · asked by argentina_mandy20 1 in Physics

somebody told me it didn't.

2007-01-18 13:15:48 · 25 answers · asked by Anonymous in Zoology

Examples also please!

2007-01-18 13:14:59 · 0 answers · asked by Anonymous in Mathematics

2007-01-18 13:12:29 · 4 answers · asked by Anonymous in Weather

If you bring an object closer to a converging mirror or a convex lens, how does that affect the attitude of the image after you hit the principal focus? Does it stay upside down, or does it flip around?

2007-01-18 13:11:49 · 1 answers · asked by Anonymous in Physics

sorry my problem is in french so my traduction might be a little bad

The point P cuts the segment AB in a "rapport" of 3:5 starting from A. Knowing that the point P is at 7/11 of the segment DE starting from E ( the points D and E are on the"prolongement" of the segment AB) what are the coordinates of the point E ?

Knowing A(-5,-3) B(8,3) D(-18,-9)

I don't know if I was clear but if you can answer thank you I just need to know what to do because frankly after findind P I have no idea what to do .

2007-01-18 13:11:31 · 2 answers · asked by kori 1 in Mathematics

2007-01-18 13:11:19 · 5 answers · asked by ksmooth_75 1 in Earth Sciences & Geology

hurry!

2007-01-18 13:10:09 · 10 answers · asked by Hopeless Hearts 2 in Chemistry

thanks for answering.

2007-01-18 13:09:48 · 2 answers · asked by amber 3 in Chemistry

to measure flowrate of general liquids.

2007-01-18 13:09:38 · 5 answers · asked by ashyco 1 in Engineering

I'm doing a science fair experiment and i need a way to remove sugar in algae produced from photosynthesis. If there is a substance or something i can do to remove the sugar, please tell me.

2007-01-18 13:09:33 · 1 answers · asked by Anonymous in Botany

does any1 know where i can find any chemistry chat rooms?

2007-01-18 13:09:23 · 2 answers · asked by shelly 3 in Chemistry

What are one, or a few--safety procedures that should be followed when conducting an experiment that involves heating protein in a test tube containing water, an acid, and a digestive enzyme.

2007-01-18 13:07:40 · 3 answers · asked by Anonymous in Biology

Find the equation of the line that is parallel to the graph of y=1/5x+2, and whose y-intercept is -5.

2007-01-18 13:07:07 · 9 answers · asked by Anonymous in Mathematics

. . . on the following geocache page: http://www.geocaching.com/seek/cache_details.aspx?guid=1aea734a-a3d3-4d09-a444-4fdb84bee15c Thanks!!

2007-01-18 13:06:59 · 1 answers · asked by ggouldson 1 in Mathematics

2007-01-18 13:06:46 · 13 answers · asked by ±±±φ±±± schön 1 in Astronomy & Space

How many pairs of electrons do the two oxygen atoms in an oxygen molecule share with each other? Explain your answer.

Thanks!

2007-01-18 13:05:18 · 1 answers · asked by football chick 6 in Biology

2007-01-18 13:04:24 · 6 answers · asked by Anonymous in Astronomy & Space

I am not too clear on this one. Is it because the fuel is being burnt after ignition so the total weight of the shuttle and fuel decreases?
Help will be appreciated.

2007-01-18 13:03:30 · 7 answers · asked by TheKingOfKnowledge 1 in Other - Science

Its not like they are ever going to succeed. Everything that can be invented has been invented. All the other discoveries will be just minor improvements.

2007-01-18 13:03:17 · 10 answers · asked by racecars 1 in Physics

chemistry

2007-01-18 13:02:48 · 3 answers · asked by jarnagin.m@sbcglobal.net 1 in Chemistry