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4 votes
2^x + 3^y = 9
2^x+1 - 3^y+1=8
find x and y​

1 Answer

5 votes

Suppose :

2^x = t ..**&**.. 3^y = u

_____________________________

t + u = 9 × 3 3t + 3u = 27

=====》

2t - 3u = 8 2t - 3u = 8

+ __________

5t = 35

5 × t = 5 × 7

t = 7

&

u = 2

________________________________

Thus :

2^x = 7 ===》 x = Log _ 2 { 7 }

3^y = 2 ===》 y = Log _ 3 { 2 }

User Amin Ba
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