A) 12.x – 27 : 24 = 28 D ) 130 – [ 5. (9- x) + 43 ] = 47 F) ( 5 ^2 = 3^2) . x + ( 5^ 2 – 3^2 ) .x -40 .x= 10^ 2

`a) => 12x-27=28.24=672`

`=> 12x=672+26=976`

`=> x=976:12=244/3`

`b) => 130-[45-5x+43]=47`

`=> 130-[88-5x]=47`

`=> 88-5x=130-47=83`

`=> 5x=88-83=5`

`=> x=5:5=1`

`c) => 16.x+16.x-40x=100`

`=> -8x=100`

`=> x=-12,5`