a, => 7x-63-30+5x=11x-6

=> 12x-93=11x-6

=> 12x=11x-6+93 = 11x+87

=> 12x-11x=87

=> x=87

b, => 7x-21-15+5x=11x-5

=> 12x-36=11x-5

=> 12x=11x-5+36 = 11x+31

=> 12x-11x=31

=> x=31

Tk mk nha

a) -3.(x-5) + 6.(x+2) = 9

-3x + 15 + 6x + 12 = 9

3x + 27 = 9

3x = -18

x = -6

b) 7.(x-9) - 5.(6-x) = -6 + 11.x

7x - 63 - 30 + 5x = - 6 +  11.x

=> 12x - 11x = - 6 + 63 + 30

x = 87

c) 10.(x-7) - 8.(x+5) = 6.(-5) + 24

10x - 70 -8x - 40 = -6

2x - 110 = - 6

2x = 104

x = 52

\(-3\left(x-5\right)+6\left(x+2\right)=9\)

\(\Rightarrow-3x+15+6x+12=9\)

\(\Rightarrow-3x+6x=9-15-12\)

\(\Rightarrow3x=-18\)\(\Rightarrow x=-6\)

1.

$-7(5-x)-2(x-10)=15$

$-35+7x-2x+20=15$

$5x-15=15$

$5x=30$

$x=30:5=6$

2.

$3(x-4)-(8-x)=12$

$3x-12-8+x=12$

$4x-20=12$

$4x=12+20=32$

$x=32:4=8$

a ) 7. ( x - 9 ) - 5( 6 - x ) = -6x + 11x

     ( 7x - 63 ) - ( 30 - 5x ) = 5x

     7x - 63 - 30 + 5x = 5x

=> 7x - 63 - 30 = 0

=> 7x = 0 + 30 + 63

=> 7x = 93

=> x = 93/7

b ) 7 . ( x - 3 ) - 5 ( 3 - x ) = 11 - 5x 

     ( 7x - 21 ) - ( 15 - 5x ) = 11 - 5x

     7x - 21 - 15 + 5x = 11 - 5x 

     7x - ( 21 + 15 ) + 5x + 5x = 11

     ( 5x + 5x + 7x ) - 36 = 11

      17x - 36 = 11

      17x = 11 + 36

      17x = 47

       x = 47/17

a)4x-5(-3+x)=7<=>4x+15-5x=7<=>4x-5x=7-15<=>-x=-8<=>x=8

b)-4(x+1)+8(x-3)=24

<=>-4x-4+8x-24=24

<=>-4x+8x=24+24+4

<=>4x=52<=>x=13

c)7(x-9)-5(6-x)=-6+11x

<=>7x-63-30+5x=-6+11x

<=>7x+5x-11x=-6+63+30

<=>x=87

\(7\left(x-9\right)-5\left(6-x\right)=-6+11x\\ \Rightarrow7x-63-30+5x+6-11x=0\\ \Rightarrow x-87=0\\ \Rightarrow x=87\)

\(7x-63-30+5x+6-11x=0\\ x-87=0\\ x=87\)

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