Δx Δp ≥ ½ ħ Δx Δp ≥ ½ ħ ’s Comments (group member since Apr 24, 2011)



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Algebra (155 new)
Nov 14, 2011 09:26PM

47038 y - y1 = m (x - x1)

y-(-3)=(8/7)(x-5)

y+3=(8/7)(x-5)

7y+21=8x-40

21+40=8x-7y

8x-7y=61
Statistics (10 new)
Oct 19, 2011 08:50PM

47038 Google Form?

survey monkey?
Algebra (155 new)
Sep 23, 2011 02:10AM

47038 6*9*x = 10x - 2
54x = 10x - 2
44x = -2
x = -2/44 = -1/22

are you sure that the problem was correct?
Algebra (155 new)
Sep 07, 2011 07:02PM

47038 hehe.. sorry.. i've just had holiday :P

well, i think your answer for the last is correct

in other way,

7n+2[2(1-n)-2(1+n)]=14
7n + 2 [ 2 {(1-n) - (1+n)} ] = 14
7n + 4 [ 1-n - 1-n] = 14
7n + 4 [-2n] = 14
7n - 8n = 14
-n = 14
n = -14
Algebra (155 new)
Sep 06, 2011 02:30AM

47038 4. yes
5. yay
9. yep
10. yuhu
11. right
12. correct
16. true
20. great
Algebra (155 new)
Aug 22, 2011 09:46PM

47038 15. yes, you did

16. 15+5[5+3(2+2)] = 15+5[5+3(4)] = 15 + 5[5+12] = 15 + 5[17] = 15 + 85 = 100
7 - 45/[5+2(6/3)] = 7-45/[5+4] = 7 - 45/9 = 7 - 5 = 2

so, 100/2 = 50
Algebra (155 new)
Jun 15, 2011 07:44PM

47038 ^ both of them i think
Geometry (104 new)
Jun 06, 2011 06:35PM

47038 which is part?
Geometry (104 new)
Jun 01, 2011 09:14PM

47038 1. because of the Exterior Angle Inequality Theorem. (ask to google)

2. because if one side of a triangle is bigger than another side, then the first sides opposite angle is also larger than the second sides opposite angle.

3. the largest is for sure, draw the lines on a piece of paper. shows you pretty well what one is the largest. the opposing angle of the largest side, if I'm not mistaken
Algebra (155 new)
May 11, 2011 05:46PM

47038 you're welcome :)
Algebra (155 new)
May 11, 2011 05:39PM

47038 @Abby: here we go...



look up for step by step. if you find it hard to understand, ask me, which part is :)
Biology (19 new)
May 11, 2011 04:04AM

May Contest! (24 new)
May 10, 2011 05:50PM

47038 Grant wrote: "what do we do 2 win the contest?!?!? whats the prize???"

yes... the prize...
Geometry (104 new)
May 09, 2011 08:31PM

47038 ah, i'm forgetting the important one,

Area is measured in "square" units.

For example, Area of a square = side times side. Since each side of a square is the same, it can simply be the length of one side squared. If a square has one side of 4 inches, the area would be 4 inches times 4 inches, or 16 square inches. (Square inches can also be written in².)

Be sure to use the same units for all measurements. You cannot multiply feet times inches, it doesn't make a square measurement. You have to convert the different unit one to other units.
Geometry (104 new)
May 09, 2011 08:21PM

47038 Sky**Rainbow Rose** wrote: "How do you find the missing measurement of these triangles?

Examples:

Area = 100 yd squared Base = 25 yd squared Height = ?

Area = 1,955 cm squared Height = 85 cm Base = ?"

____________________________________________________

Okay, the formula for area of a triangle given by

A = ½ x b x h


A = area
b = base
h = height

or, area of the triangle equals one half times the base times the height. so, from the exercises:

1)
A = 100 yd²
b = 25 yd
h?
re-arrange the formula for area of a triangle:

A = ½ x b x h ... multiple both sides by 2
2A = b x h ...... divide both sides by "b"
2A/b = h

so, we get the formula to find the height
h = 2A/b
plug in the numbers
h = 2 (100) /25 = 200/25 = 8

thus, the height of the triangle is 8 yard (the unit is must be equal to others)

2)
A = 1,955 cm²
h = 85 cm
so,

A = ½ x b x h ... multiple both sides by 2
2A = b x h ...... divide both sides by "h"
2A/h = b

so,
b = 2A/h , plug in the numbers
b = 2 (1,955) / 85 = 3910/85 = 46

the base of the triangle is 46 cm
Geometry (104 new)
May 09, 2011 06:53AM

47038 ^ errr. is it a formula for volume of a cube? not formula for surface area of a cube?
Algebra (155 new)
May 08, 2011 09:50AM

47038 to get 3rd answer, you must see the point B (-2,-4), C (6, -4)

the general form of a line equation is
y = ax +b


plug in point B to the general equation:
(-4) = a (-2) + b
-4 = -2a + b ...................... (1)

plug in point C to the general equation
(-4) = a (6) + b
- 4 = 6a + b ...................... (2)

so, we have two equations for (1) and (2)

- 4 = -2a + b = 6a + b
-2a + b = 6a + b
-2a = 6a

the only possibility that comply this equation, "a" must be zero.
-2 (0) = 6(0) = 0

so, we get a = 0

subtitute "a" to (1) equation
-4 = -2a + b
-4 = -2(0) + b
b = -4

in other way, you can find it by subtitute "a" to 2nd equation
-4 = 6(a) + b
-4 = 6(0) + b
b = -4

you get a and b, so, plug them to the general equation

y = ax + b
y = (0)x + (-4)
y = 0 -4
y = -4

proven!
Algebra (155 new)
May 08, 2011 09:34AM

47038 actually, the first and the second answer are similiar. but in 2nd, we don't have m or slope. so, to get m, we use a formule to find it.

The slope m of the line through the
points (x1, y1) and (x2, y2) is given by


so, from the points A(1, 5), B(-2, -4), we must label the points as x1, y1, x2, y2. Label the points as x1 = 1, y1 = 5, x2 = -2, and y2 = -4.
To find the slope m of the line segment joining the points, use the slope formula

m = [(-4)- 5]/[(-2)-1)] = -9/-3 = 3

or, you can label point A as (x2,y2) and B as (x1, y1)
x1 = -2, y1 = -4, x2 = 1, y2 = 5
so,
m = [5 - (-4)]/[1 - (-2)] = 9/3 = 3


After you got "m", you use formula in first answer.
y - y1 = m (x - x1)
m is the calculated slope, and (x1, y1) are the coordinates of the given point (you can use point A or point B, it gives same result as showed in 2nd answer)
Algebra (155 new)
May 08, 2011 05:45AM

47038 which part is don't u get?
Algebra (155 new)
May 05, 2011 08:36PM

47038 1. Use the point-slope form of the equation of a line:
y - y1 = m (x - x1)


m is the given slope, and (x1, y1) are the coordinates of the given point.

Then solve the result for y to put it into slope-intercept form.

m = -1 ; (x1,y1) = (6,-4)

so
y - y1 = m (x-x1)
y - (-4) = -1 (x - 6)
y + 4 = -x + 6
y = -x - 4


2. Point-Slope Form: y - y1 = m(x - x1)
x1: x coordinate of a point they give you [doesn't matter which point]
y1: y coordinate of a point they give you [has to be the coordinate that came with x1]
m: slope

You could do point-slope form directly, but you don't have slope

Slope: (y2 - y1)/(x2 - x1) [It doesn't matter which point you choose to by y1 or y2, as long as y1 corresponds to x1 and y2 corresponds to x2 ]

(5-(-4))/(1-(-2))= 9/3= 3

Choose a point [either A or B] and plug everything in:
Using point A: y-5=3(x-1) ---> y = 3x + 2
Using point B: y+4=3(x+2) ---> y = 3x + 2

3. it's simple
y = -4

There is no change in the Y-coordinates, therefore Y will always equal the same thing, regardless of X, in this case, negative four.
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