Solve by elimination method :-
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Answered by
48
Hey Tanu !
Here is your solution :
2^x + 3^y = 17 ------- ( 1 )
2^( x + 2 ) - 3^( y + 1 ) = 5 ------- ( 2 )
By multiplying in ( 1 ) by 3,
( 2^x ) 3 + ( 3^y ) 3 = 51
( 2^x )3 + 3^( y + 1 ) = 51 -------- ( 3 )
Adding ( 2 ) and ( 3 ),
2^( x + 2 ) - 3^( y + 1 ) = 5
( 2^x ) 3 + 3^( y + 1 ) = 51
_____________________
2^( x + 2 ) + 2^( x ) 3 = 51 + 5
By taking, 2^x as common in L.H.S,
( 2^x ) ( 2^2 + 3 ) = 56
( 2^x ) ( 4 + 3 ) = 56
( 2^x ) 7 = 56
2^x = 56 ÷ 7
2^x = 8
2^x = ( 2)^3
As bases are equal, so exponent will be also equal.
x = 3.
By substituting the value of x in ( 1 ),
2^x + 3^y = 17
2^3 + 3^y = 17
8 + 3^y = 17
3^y = 17 - 8
3^y = 9
3^y = 3^2
As bases are equal, so exponent will be also equal.
y = 2.
So, x = 3 and y = 2.
===================================
Hope it helps !!
Here is your solution :
2^x + 3^y = 17 ------- ( 1 )
2^( x + 2 ) - 3^( y + 1 ) = 5 ------- ( 2 )
By multiplying in ( 1 ) by 3,
( 2^x ) 3 + ( 3^y ) 3 = 51
( 2^x )3 + 3^( y + 1 ) = 51 -------- ( 3 )
Adding ( 2 ) and ( 3 ),
2^( x + 2 ) - 3^( y + 1 ) = 5
( 2^x ) 3 + 3^( y + 1 ) = 51
_____________________
2^( x + 2 ) + 2^( x ) 3 = 51 + 5
By taking, 2^x as common in L.H.S,
( 2^x ) ( 2^2 + 3 ) = 56
( 2^x ) ( 4 + 3 ) = 56
( 2^x ) 7 = 56
2^x = 56 ÷ 7
2^x = 8
2^x = ( 2)^3
As bases are equal, so exponent will be also equal.
x = 3.
By substituting the value of x in ( 1 ),
2^x + 3^y = 17
2^3 + 3^y = 17
8 + 3^y = 17
3^y = 17 - 8
3^y = 9
3^y = 3^2
As bases are equal, so exponent will be also equal.
y = 2.
So, x = 3 and y = 2.
===================================
Hope it helps !!
vipun:
mean
Answered by
12
heya here is your answer please mark me as brainlest
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