What is the answer of 7 over 2x - 5 over 3x=11?

2009-01-21 10:15 am
i really don't know the answer i already did it 3 times! :(

回答 (7)

2009-01-21 10:32 am
✔ 最佳答案
Do you mean 7/2x - 5/3x = 11?
Multiply with 6x
21 - 10 = 66 x
11 = 66 x
x = 11/66 = 1/6
2016-11-07 12:02 pm
2 = Squareroot (2x-5) - Squareroot(x-2) sq. the two sides of the equation 4 = [Squareroot (2x-5) - Squareroot(x-2)]^2 4 = 2x-5 + x-2 - 2*squareroot [(2x-5)(x-2)] 4 = 3x-7 - 2*squareroot [(2x-5)(x-2)] 3x-7 = 4 + 2*squareroot [(2x-5)(x-2)] 3x-11 = 2*squareroot [(2x-5)(x-2)] Sqaure the two sides (3x-11)^2 = 4(2x-5)(x-2) 9x^2 - 66x + 121 = 4(2x^2 - 9x + 10) 9x^2 - 66x + 121 = 8x^2 - 36x + 40 9x^2 - 66x + 121 - ( 8x^2 - 36x + 40) = 0 9x^2 - 66x + 121 - 8x^2 + 36x - 40 = 0 x^2 - 30x + 80 one = 0 Factorise (x-3)(x-27) = 0 x=3 or x=27 x=3 is rejected because it would not paintings. in case you substitute x=3 into Squareroot (2x-5) - Squareroot(x-2), you wil get a million-a million, it rather is comparable to 0 and not 2 as given interior the equation for this reason, x=27
2009-01-21 10:44 am
7
--- = 11
2x-5
---
3x

7/(2x-5) x 1/3x=7
[7/(2x-5)3x=11] LCD IS (2x-5)3x
7=11(3x(2x-5))
7=11(6x^2-15x)
7=66x^2-165x
66x^2-165x-7=0
using quadratic formula

x=-b+/-sqrt(b^2-4ac)/2a
x=-(-165)+/-sqrt((-165)^2-4(66)(-7)]/2(66)
x= 165+/-sqrt[27225+1848]/132
x=165+/-sqrt[29073]/132
x1=165+sqrt(29073]/132 x2=165-sqrt(29073)/132
x1=2.5417 x2=-0.041728 answer//
2009-01-21 10:32 am
7/(2x) - 5/(3x) = 11
6x[7/(2x) - 5/(3x)] = 6x[11]
3(7) - 5(2) = 66x
66x = 21 - 10
66x = 11
x = 11/66
x = 1/6
2009-01-21 10:31 am
((7/(2x-5))/3x)=11

(7/3x(2x-5))=11

7=11((6x^2)-15x)

6x^2-15x=7/11

2x^2-5x-7/33=0

this is a quadratic equation having 2 values of x

Solving for x, we get,

x=2.54 or x=-0.04
參考: Casio fx-95 Calculator and my knowledge
2009-01-21 10:24 am
22x-21x=55
x=55
2009-01-21 10:18 am
x=55


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