Need help with a algebraic fraction Watch

MisterE
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#1
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#1
2x/3x+1 - 5/x+3 = 0

i got x=1 , i think its wrong, please help
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insparato
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#2
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2x/3x+1 - 5/x+3 = 0

2x/3x+1 =5/x+3

2x(x+3)= 5(3x+1)

2x^2 +6x = 15x + 5

2x^2 - 9x - 5 = 0

(2x + 1 )(x - 5) = 0

x = -1/2 x = 5
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MisterE
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#3
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Hey, thanks for the help! I've got another problem which i cant tackle though!

x-1/2 - x-3/5 = 1

please help! I just cant do algebraic fractions in maths and am practicing so hard!!
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danniella
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#4
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Hello!

(x-1)/2 - (x-3)/5 = 1
Multiply everything by 10.
5(x-1) - 2(x-3) = 10
5x-5 - (2x-6)=10
5x - 5 - 2x + 6 = 10
3x + 1 = 10
3x = 9
x=3

love danniella
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MisterE
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#5
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2x^2 - 9x - 5 = 0

(2x + 1 )(x - 5) = 0

x = -1/2 x = 5



I dont understand this part. I was taught that the brackets should times to make 5 and add or subtract to make 9. I see it times to make 5 but how does it add/subtract to make 9?
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MisterE
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#6
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Could i also ask why the -6 turned into a +6 in this part danniella?
5x-5 - (2x-6)=10
5x - 5 - 2x + 6 = 10
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CalculusMan
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#7
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5x-5 - (2x-6)=10

The negative sign infront of the bracket

-(2x - 6) = -2x + 6
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CalculusMan
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#8
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(Original post by MisterE)
2x^2 - 9x - 5 = 0

(2x + 1 )(x - 5) = 0

x = -1/2 x = 5



I dont understand this part. I was taught that the brackets should times to make 5 and add or subtract to make 9. I see it times to make 5 but how does it add/subtract to make 9?
It is supposed to add to -9 and the product should be +5

2x * -5 = -10, x * 1 = 1, -10 + 1 = -9, as required.
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