MizoriesKun 4b-2a          -2(a-2b)
------------ = -------------- = -2*5= -10
5b+3a         5b+3a
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5a-10b      5(a-2b)       5
----------- = ------------- = ---- *5=  25/3
15b+9a    3(5b+3a)      3
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a²-4ab+4b²             (a-2b)²
---------------------- = ------------ = 5²=25
9a²+30ab+25b²     (3a+5b)²

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  5b+3a             5b+3a
( -----------)³ = (-------------)³ = (-1/5)³= -1/125
   2b-a              -1*(a-2b)