Calcule le nombre x . aidez moi svp et merci A) 5(4-x)=12 B). 3(2x+5)=20 C). (3-x)2=6 Merci d avance

Hola,

5(4 - 1x) = 12
5 * 4 + 5 * -x = 12
20 - 5x = 12
-5x = 12 - 20
-5x = -8
x = 8/5

3(2x + 5) = 20
6x + 15 = 20
6x = 20 - 15
6x = 5
x = 5/6

2(3 - x) = 6
6 - 2x = 6
-2x = 6 - 6
-2x = 0
x = 0/-2 = 0