Răspuns:
a) 6x=13+7 , 6x=20÷6 , x = 20/6 = 10/3
b) x/-radical 14 = 7 radical2, x= 7radical 2 ×radical14 , x= 7 radical28 = 14 radical7
c) 7x-3x=22,10x=22 ÷10 , x = 11/5
d) 12x-7x=1-16 , 4x = -15 ÷4 , x= -15/4
e) x/5-4x/15= 1/9 , (3x-4x)/15 = 1/9 , -x/15 =1/9 ,( -3x /45 = 5/45) ×45 , -3x = 5 , x= -5/3