Algebra Equation. Help. Please. (1 Viewer)

clarebear22

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Argh.
Maths is annoying.
Anyone know how to do this equation?
Please help it's driving me insane.
Thanks. :)

2y - 5 - 2 = 3x + 2
3 _______ 5
 

lyounamu

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clarebear22 said:
Argh.
Maths is annoying.
Anyone know how to do this equation?
Please help it's driving me insane.
Thanks. :)

2y - 5 - 2 = 3x + 2
3 _______ 5
You cannot solve the question because you have two variables with nothing else given. Did you mean (2x-5)/3 - 2 = (3x+2)/5 ?
 

PC

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Equation is:

(2x – 5)/3 – 2 = (3x + 2)/5

What I would do first is get all the fractions on to one side.
Add 2 to both sides, then subtract the fraction on the right from both sides.

(2x – 5)/3 – (3x + 2)/5 = 2

Now look for a common denominator on the left. It's 15, so change both the fractions.
In the first we multiply top and bottom by 5 and in the second we multiply top and bottom by 3.

5(2x – 5)/15 – 3(3x + 2)/15 = 2

Because the denominators are the same we can combine the fractions.

[5(2x – 5) – 3(3x + 2)]/15 = 2

Now multiply both sides by 15.

[5(2x – 5) – 3(3x + 2)] = 30

We should be right from there.

[5(2x – 5) – 3(3x + 2)] = 30
10x – 25 – 9x – 6 = 30
x – 31 = 30
x = 61
 

bored of sc

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You could multiply everything by 15 at the start to destroy the fractions first up.
 

PC

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Yeah, that's the standard textbook or teacher method. If you can do it, that's the best way, but many students seems to stuff up that first step somewhere.
 

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