Răspuns:
a. - 6+3x=0
3x=6
x=2
Verificare: -6+3•2=0
-6+6=0
0=0
b. - 3x+3=0
-3x=-3 |:-3
x=1
Verificare: -3•1+3=0
- 3+3=0
0=0
c. - 9x+18=0
-9x=18 |:9
-x=2 |:-1
x=-2
Verificare: -9•-2+18=0
- 18+18=0
0=0
d.5x-20=0
5x=20
x=4
Verificare: 5•4-20=0
20-20=0
0=0
e.
[tex] \sqrt{5} x + \sqrt{20} = 0 \\ \sqrt{5} x = - \sqrt{20} \\ x = - \sqrt{4} [/tex]
Verificare :
[tex] \sqrt{5} \times - \sqrt{4} + \sqrt{20} = 0 \\ - \sqrt{20} + \sqrt{20} = 0 \\ 0 = 0[/tex]
f.
[tex] \sqrt{3} x - \sqrt{3} = 0 \\ \sqrt{3} x = \sqrt{3} \\ x = \sqrt{3} \div \sqrt{3} \\ x = 1[/tex]
Verificare :
[tex] \sqrt{3} \times 1 - \sqrt{3} = 0 \\ \sqrt{3} - \sqrt{3} = 0 \\ 0 = 0[/tex]
g.
[tex] \sqrt{2} x - \sqrt{18} + 2 \sqrt{2} = 0 \\ \sqrt{2} x - 3 \sqrt{2} + 2 \sqrt{2 } = 0 \\ \sqrt{2} x - 1 \sqrt{2} = 0 \\ \sqrt{2} x = \sqrt{2} \\ \times = 1[/tex]
[tex] \sqrt{2} \times 1 - \sqrt{18} + 2 \sqrt{2} = 0 \\ 1 \sqrt{2} - 3 \sqrt{2} + 2 \sqrt{2} = 0 \\ 0 = 0[/tex]
h.
[tex](5 - \sqrt{7} ) - 5 + \sqrt{7} = 0 \\ 5 - \sqrt{7 } - 5 + \sqrt{7} = 0 \\ 0 = 0[/tex]
Sper ca te am ajutat!!
