ricom39

1 Questions
19 Answers

0

1054

3

+42

old algebra

Write 10+sqrt(84) in the form (a+b)^2

ricom39 Mar 15, 2012

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Look up how many Joules are needed to warm 1 g water 1 degree.
Suppose y J
You will need totally 800 x 88 x y Joules = T Joules
1 Joule = 1 Ws
Divide T trough 2000 and you'll find the number of seconds.

As I remember this it will be about 10 minutes.

ricom39May 12, 2013

+42

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sin ( -1) = -0,017452402

ricom39May 12, 2013

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Write your equations in the form y = rx + s
Where r is saying something on the direction of the line.
The same r, so the same direction (parallel)
r1 x r2 = -1 then perpendicular

Try now!

y = 3/8 x + 14/8 r1 = 3/8
y = -32/12 x - 15/12 => y = -8/3 x - 5/4 r2 = - 8/3
r1 * r2 = ?
3/8 * -8/3 = -1

Perpendicular!

ricom39Feb 25, 2013

+42

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2u-9=5 or 2u-9=-5
2u=14 or 2u=4
u=7 or u=2
S= {2, 7}

ricom39Dec 18, 2012

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a^2 + b^2 = c^2
(3x)^2 + (4x)^2 = 75^2

9x^2 + 16x^2 = 75^2
25x^2 = 25^2.3^2
x^2 = 5^2.3^2
x=15
So the length of the sides are 45 and 60

ricom39Nov 28, 2012

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4x^2 - 4x^2 - 12x - 9 = 8x - 28 - 1
-20x = -20
x = 1

ricom39Nov 26, 2012

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Quite simpel:

2/12 + 9/12 + 4/12 = 15/12 answer: 1/3

2/12 + 5/12 + 8/12 = 15/12 answer: 5/12

ricom39Nov 10, 2012

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There is a formule: S = 1/2 n (n + 1)

Here is n = 100

ricom39Nov 5, 2012

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4(x-2)/(x-3) + 3/x = -3/x(x-3)

4x(x-2)/x(x-3) + 3(x-3)/x(x-3) = -3/x(x-3)

x cannot be 0 or 3

4x^2 - 8x + 3x - 9 = -3

4x^2 -5x -6 = 0

(x-2)(4x+3) = 0

x = 2 or x = - 3/4

ricom39Nov 5, 2012

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1% = 2,37 (divided through 100)
34% = 34 x 2,37 = 80,58

ricom39Oct 11, 2012

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5^(-4) or 1/(5^4) or 1/625
Divide: subtract the exponents, so 9 - 13 = -4

ricom39Oct 11, 2012

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I think your problem is not complet.
It should be: 6x^2 - 54 = 0
So my solution will be:
6x^2 = 54
x^2 = 9
x = 3 or x = -3
S = {3, -3}

ricom39Oct 11, 2012

+42

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Suppose the shadow x feet
Then 16 : 6 = (12 + x) : x
16x = 6 (12 + x)
16x = 72 + 6x
10x = 72
x = 7,2 feet

ricom39Aug 8, 2012

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no calculator needed:
divide both sides through 4
you get x+1 > 4
x>3
simpel?

ricom39Jun 12, 2012

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(a+b)(x+y) should be right

ricom39Jun 12, 2012

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The right answer is:
if x < ½ then -2x + 1
if x > ½ then 2x - 1
if x = ½ then both are right, no differance

ricom39Apr 9, 2012

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P=U.I I=U/R hence P= U^2/R and R=U^2/P

So R = 119.3^2 /144 = 98,8 Ohm

ricom39Mar 27, 2012

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My solution: (a+b)^2= a^2+b^2+2ab
10 + sqrt(84) = 10 + 2 (sqrt(21))
so: a^2 + b^2 = 10 and ab=sqrt(21)
solution: 7 + 3 = 10 and sqrt(7)*sqrt(3)=sqrt(21)
My answer is: (sqrt(7)+sqrt(3))^2

ricom39Mar 22, 2012

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Can nobody solve this problem?

ricom39Mar 21, 2012