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2) 3x − 7, 5 + 2x = 2, 5x − 7, 5 − 10 ;
0, 4x − 0, 5x = −2, 5 + 2, 8 ; −0, 1x = 0, 3 ; x = 0, 3 : ( −0, 1) ; x = −3 ;
3)
5x − 2, 5x = −10 ; 2, 5 = −10 ; x = −10 : 2, 5 ; x = −4 ;
2⋅3 2 ⋅3 4 ⋅5 4 ⋅1 3 x+ − x+ =1 ; 3⋅2 3 ⋅ 5 5 ⋅12 5⋅2 5 1 3 4 x− x =1 − ; 3 5 5 2 4 x= ; 3 5 4⋅3 x= ; 5⋅2 6 x= ; 5 1 x =1 . 5
1167. 1) −54x − 9 = −90x − 117 ; −54x + 90x = −117 + 9 ; 36x = −108 ; x = ( −108 ) : 36 ; x = −3 ;
2) 1, 2x + 0, 6 = −5, 4x + 7, 2 ; 1, 2x + 5, 4x = 7, 2 − 0, 6 ; 6, 6x = 6, 6 ; x = 6, 6 : 6, 6 ; x =1 .
1168. 1) −1, 4x + 8, 4 = 28x + 8, 4 ; −1, 4x − 28x = 0 ; −29, 4x = 0 ; x=0 ;
2) 1, 04x − 3, 64 = −4, 68x + 3, 51 ; 1, 04 + 4, 68x = 3, 51 + 3, 64 ; 5, 72x = 7, 15 ; x = 1, 25 .
1169. 1)
1170. 1)
x + 0, 4 0, 7 − x = ⋅ 24 ; 8 3 24 ⋅ ( x + 0, 4 ) ( 0, 7 − x ) ⋅ 24 = ; 8 3 3x + 1, 2 = 5, 6 − 8x ; 3x + 8x = 5, 6 − 1, 2 ; 11x = 4, 4 ; x = 4, 4 : 11 ; x = 0, 4 ;
(x
8 ) ⋅ 3 = ( x + 2) ⋅7 ;
3x − 24 = 7x + 14 ; 3x − 7x = 14 + 24 ; −4x = 38 ; 38 x=− ; 4 x = 9, 5 ;
2)
МАТЕМАТИКА
1166. 1) 0, 4x − 1, 2 − 1, 6 = 0, 5x − 2, 5 ;
5 5x + 6 = ; 6 2x + 3, 2 5 ⋅ ( 2x + 3, 2 ) = ( 5x + 6 ) ⋅ 6 ; 10x + 16 = 30x + 36 ; 10x − 30x = 36 − 16 ; −20x = 20 ; x = −1 .
2)
( x − 10 ) ⋅ 4 = 15 ⋅ ( x − 1, 2 ) ; 4x − 40 = 15x − 18 ; 4x 15x = 18 + 40 ; −11x = 22 ; x = −2 .
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