Rezolvati ecuatiile:a)4(x+5)-5(x+3)=6x-5(x+1)
b) 4x+3(x+4)=5(x-1)-6(x+3)+11
c) 6(x+3)-7(x+5)=4(x+1)-2(x+6)+12
d) 2(5x-6)-3(4x-7)=21-4(2x-5)
Răspunsuri la întrebare
a ) 4( x + 5 ) - 5( x + 3 ) = 6x - 5( x + 1 )
4x + 20 - 5x + 15 = 6x - 5x - 5
4x + 20 - 15 = 6x - 5
4x + 5 = 6x - 5
4x - 6x = -5 - 5
-2x = -10
x = 5
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b ) 4x + 3( x + 4 ) = 5( x - 1 ) - 6( x + 3 ) + 11
4x + 3x + 12 = 5x - 5 - 6x - 18 + 11
7x + 12 = -x - 12
7x + x = -12 - 12
8x = -24
x = -3
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c ) 6( x + 3 ) - 7( x + 5 ) = 4( x + 1 ) - 2( x + 6 ) + 12
6x + 18 - 7x - 35 = 4x + 4 - 2x - 12 + 12
-x - 17 = 2x + 4
-x - 2x = 4 + 17
-3x = 21
x = -7
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d ) 2( 5x - 6 ) - 3( 4x - 7 ) = 21 - 4( 2x - 5 )
10x - 12 - 12x + 21 = 21 - 8x + 20
10x - 12 - 12 x = -8x + 20
-2x - 12 = -8x + 20
-2x +8x = 20 + 12
6x = 32
x = 16 / 3
a)
4 ( x + 5 ) - 5 ( x + 3 ) = 6 x - 5 ( x + 1 )
4 x + 20 - 5 x - 15 = 6 x - 5 x - 5
- x - x = - 5 - 5
- 2 x = - 10
x = ( - 10 ) : ( - 2)
x = 5
___________________________
b)
4 x + 3 ( x + 4 ) = 5 ( x - 1 ) - 6 ( x + 3 ) + 11
4 x + 3 x + 12 = 5 x - 5 - 6 x - 18 + 11
7 x + x = - 12 - 12
8 x = - 24
x = - 24 / 8
x = - 3
_____________________
c)
6 ( x + 3 ) - 7 ( x + 5 ) = 4 ( x + 1 ) - 2 ( x + 6 ) + 12
6 x + 18 - 7 x - 35 = 4 x + 4 - 2 x - 12 + 12
- x - 2 x = 4 + 17
- 3 x = 21
x = 21 : ( - 3)
x = - 7
_________
d)
2 ( 5 x - 6 ) - 3 ( 4 x - 7 ) = 21 - 4 ( 2 x - 5)
10 x - 12 - 12 x + 21 = 21 - 8 x + 20
- 2 x + 8 x = 21 - 21 + 20 + 12
- 2 x + 8 x = 20 + 12
6 x = 32
x = 32 / 6 = 16 / 3