Răspuns:
Explicație pas cu pas:
a) 3(x+4)=5x 3x+12=5x 2x=12 x=6
b)10x-10=3 10x=13 x=1,3
c)4(x+2)=x 4x+9=x -3x=9 x=-3
d)7,5=x/2/2 7,5=x/4 x=7,5·4=30
e) 11,5x-51,75=2,5x+11,25 ⇒ 9x=51,75+11,25 ⇒9x=63 x=7
f)1/5=(2-x)/x x=5(2-x) x=10-5x 6x=10 x=5/3
