Always multiply with the smallest factor of all the numbers.

1. 2x/7 + 3x/2 = 25/7 [The smallest factor is 14 so multiply straight through with 14]

then 4x + 21x = 50

25x = 50

x = 2

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2. (x-2)/2 - (x + 2)/4 = 1/2 [the smallest factor is 4]

then 2x - 4 - x - 2 = 2

x - 6 = 2

x = 8

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3. 2,4x - 1,2 x = 4,8

[Now we only simplify]

1,2x = 4,8

[divide by 1,2 on both sides]

and then x = 4

Hope this helps!