Question

8.(x+2)-6.x=140

10.(x-4)-8.(x+2)=12

x.(x-3)=6.(x-3)

 

Answer 1

10( x - 4 ) - 8( x + 2 ) = 12

10x - 40 - 8x + 16 = 12 

=> x( 10 - 8 ) - 40 + 16 = 12

           2x - 40 + 16 = 12

            2x - 40 = -4

                   2x = -4 + 40 = 36

                     x = 36 : 2 = 18 

Answer 2

8.(x+2)-6.x=140

8( x + 2 ) - 6x = 140

8x + 16 - 6x = 140

x( 8 - 6 ) + 16 = 140

 2x + 16 = 140

2x = 140 - 16

2x = 124

 x = 124 : 2

x= 62

10.(x-4)-8.(x+2)=12

10x - 40 - 8x + 16 = 12 

x( 10 - 8 ) - 40 + 16 = 12

2x - 40 + 16 = 12

2x - 40 = 12-16

2x - 40 = -4

2x = -4 + 40

2x = 36

x = 36 : 2

x= 18 

x.(x-3)=6.(x-3)

 

Answer 3

x( x - 3 ) = 6( x - 3 ) 

x² - 3x = 6x - 18

=> x² - 3x - 6x + 18 = 0

     x( x - 3 - 6 ) = -18

     x( x - 9 ) = -18

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