Question

найдите корень уравнения :
1) 9( x - 1) = x + 15
2) (11x + 14) - (5x - 8) = 25
3) 12 - 4( x - 3 ) = 39 - 9x
4) 2( 3x + 5 ) - 3(4x - 1 ) = 11,8

Answer 1

1)
9( x - 1) = x + 15
9x-9=x+15
9x-x=15+9
8x=24
x=24:8
x=3
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2)
(11x + 14) - (5x - 8) = 25
11x+14-5x+8=25
6x+22=25
6x=25-22
6x=3
x=3:6
x=0,5
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3)
12 - 4( x - 3 ) = 39 - 9x
12-4x+12=39-9x
24-4x=39-9x
-4x+9x=39-24
5x=15
x=15:5
x=3
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4)
 2( 3x + 5 ) - 3(4x - 1 ) = 11,8
6x+10-12x+3=11,8
-6x+13=11,8
6x=13-11,8
6x=1,2
x=1,2:6
x=0,2