Another approach ---- take log each side.
2x⋅5y=100→xlog2+ylog5=2
2y⋅5x=1000→ylog2+xlog5=3
After this we may solve it like a linear equation!!
Add the 2 equations up:xlog2+ylog2+xlog5+ylog5=5(x+y)(log2+log5)=5←Factorization(x+y)(log10)=5←Property of logarithmsx+y=5
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