Mathematics - 21 December 2007

please i need help

2007-12-21 14:47:42 · 7 answers · asked by Timothy B 1

If the selling prices of homes in a neighborhood are normally distributed around a mean of $315,000, with a standard deviation of $25,500, what is the probability of a house in this neighborhood costing between $369,000 and $388,000? Show your work.

2007-12-21 14:10:18 · 3 answers · asked by Nina 1

I have mid term review and I would like to make sure that my answers are correct so that i learn from what is right and not wrong. Also, some of these questions i just don't understand how to find the answer or even what they're asking for. So here are a few of the questions I don't understand, and if you could solve them and explain in great detail how you got the answer i would appreciate it! [= please only answer the one's you know; also; best answer will also go to great detail
-Thank you!

Two adjacent sides of a rhombus are represented by 5x+7 and 6x-1. Find the value of x.

If y varies directly as x and y=24 when x=4, find the value of y when x=9.

Solve for x in terms of a, b, and c:
ax-3b=c

The line whose equation is y=4x+2 has a y-intercept whose coordinates are:
(1) (0,0) (2) (0,2) (3) (4,0) (4) (0,4)

Which equation represents the lin parallel to the y-axis and 4 units to the left of the y-axis?
(1) x=4 (2) x=-4 (3) y=-4 (4) y=4

more added later

2007-12-21 13:17:03 · 6 answers · asked by ohhlaalaa 2

2007-12-21 13:11:33 · 14 answers · asked by Xavier T 2

Which one of the following is not true??

a)2x^2-x-6=(2x+3)(x-2)

b)2x^2+x-6=(2x-2)(x+3)

c)2x^2-11x-6=(2x+1)(x-6)

d)2x^2+11x-6=(2x-1)(x+6)

2007-12-21 13:07:42 · 7 answers · asked by Anonymous

how do you get the proof that f(X) = 3 and its derivative is 0, zero. I mean its obvious that its a constant and its derivative is always 0, but how do you prove it?

hint: by using (f(x + dx) - f(x) )/ dx as lim dx goes to 0

2007-12-21 13:05:06 · 5 answers · asked by john_lu66 4

I believe that a 100% reduction means that you have nothing left, but others have said it cuts it in half. To me that math doesn't add up, since half=1/2=.5 and .5 is the same as saying 50%...therefore, a cut in half cannot be a 100% reduction.

2007-12-21 13:04:52 · 6 answers · asked by Wesley S 1

2007-12-21 12:36:24 · 8 answers · asked by lollipop2eat2003 2

2007-12-21 12:32:41 · 7 answers · asked by lollipop2eat2003 2

The difference of two positive numbers is 5 and the sum of their squares is 233. Which pair of numbers is the solution to this word problem?

a) The two numbers are 8 and 13.

b) The two numbers are 7 and 12.

c) The two numbers are 6 and 11.

d) The two numbers are 9 and 14

The length of a rectangle is 6 cm less than twice its width. Find the dimensions of the rectangle if its area is 108 cm2. Which equation can you use to solve this problem?

a) w(2w + 6w) = 108

b) w(2w – 6w) = 108

c) w(2w – 6) = 108

d) w(2w + 6) = 108

2007-12-21 12:31:45 · 5 answers · asked by Anonymous

2007-12-21 12:21:19 · 11 answers · asked by liz k 1

2007-12-21 12:12:35 · 1 answers · asked by helo 1

I'm not that good in Math...please help me. I don't think my teachers explain it well.

Question-
Vertex angle A of isosceles triangle ABC measures 20 degrees more than 3 times angle B. Find angle C.

^ I don't understand! Please help

2007-12-21 11:59:35 · 3 answers · asked by someone 1

4x -7- x=8
19=5x-4x+9
-68=6x+x+2
-6-4x-6x=54
x2-8x-20=0

2007-12-21 11:56:36 · 10 answers · asked by Long N 3

2007-12-21 11:51:18 · 5 answers · asked by nightowl 2

2007-12-21 11:12:51 · 3 answers · asked by christi 1

Thanks!!!!!!!!!!!!

2007-12-21 10:51:03 · 11 answers · asked by codebreaker1011 2

plz help me

2007-12-21 10:45:33 · 12 answers · asked by dag652000 2

Notice that the digits 1 through 9 are used in order to arrive at 106.
Question for you is - using 1 through 9 in order, and using only addition or subtraction, create an equation that equals 100.

2007-12-21 10:25:41 · 6 answers · asked by cliveyboyuk 3

PLEASE EXPLAIN - SOLVE - U GET BEST ANSWER

-11x = 395 + y
14y = -634 - 10x

2007-12-21 10:01:18 · 8 answers · asked by Jaz 'ma' Taz 2

I have to make and design a T-shirt for my AP Calc class. It's supposed to "show effort" and be creative, funny, innovative, and/or witty. Being not exactly a creative person, I am totally stuck. Please help?

2007-12-21 09:46:00 · 11 answers · asked by trinity l 1

Given f(x) = 4x + 2, find f(a + 3).

2007-12-21 09:42:17 · 5 answers · asked by misha 1

Can you please help me with this? Thanks!

2007-12-21 09:40:34 · 2 answers · asked by codebreaker1011 2

What if a stick magnet at 1 side is somehow cut in half and turn in oppiosite sides.Will the newly form ends will become plus plus or minus plus?
+l==>?_ _?
ol==> o V
-l==> o-l
*O's means nothing

2007-12-21 09:24:46 · 4 answers · asked by dracomaster101 1

1. 27 +sqrt 297 divided by 9





2. solve and check this problem
sqrt y +18 =4

2007-12-21 09:15:06 · 6 answers · asked by God Bless America!~ 4

1. (7 + sqrt 3) (7-sqrt 3)



2. sqrt 75a^2 divided by sqrt 5

2007-12-21 09:12:36 · 5 answers · asked by God Bless America!~ 4

a sqrt 8 -3 sqrt 2a^2

2007-12-21 09:10:14 · 8 answers · asked by God Bless America!~ 4

This is the makeup for a grade

A is 40%
B is 40%
C is 20 %

(note that these numbers are grades) A=90 B=90 and C=95

what would the grade be in percentage

2007-12-21 08:59:34 · 4 answers · asked by The Lone Trumpeter 2

According to the Wall Street Journal, 14,200,000 videotape copies of Walt Disney's Fantasia have been sold to date. Write that number in scientific notation?

A. 142 x 1,000,000
B. 1.42 x 106

C. 1.42 x 107

D. 142 x 107

2007-12-21 08:50:42 · 5 answers · asked by yummyummy 1

If a ball is thrown vertically upward from a height of 5 ft. with an initial velocity of 80 ft/sec, its height h after t seconds is given below. How long does it take the ball to return to the ground? Round to two decimal places.
h=-16t^2+80t+5

2007-12-21 08:42:48 · 4 answers · asked by lynne 2