Explicație pas cu pas:
40 - x = 13
x = 40 - 13
x = 27
12x = 132
x = 132 : 12
x = 11
189 : x = 21
x = 189 : 21
x = 9
5x - 6 = x + 6
5x - x = 6 + 6
4x = 12
x = 12 : 4
x = 3
[tex] {2}^{3x + 2} = {4}^{10} \\ {2}^{3} \times {2}^{x} \times {2}^{2} = {2}^{20} \\ {2}^{x} = {2}^{20} \div {2}^{3} \div {2}^{2} \\ {2}^{x} = {2}^{15} \\ x = 15[/tex]
