Question

Afla "a" din egalitatea: 412:4-{72-2x[36-4x(9:a)] +5x12}:6 =89

Answer 1

 412:4-{72-2x[36-4x(9:a)] +5x12}:6 =89
103-{72-2x[36-4x(9:a)] +60}:6 =89
{72-2x[36-4x(9:a)] +60}:6 =103-89
{72-2x[36-4x(9:a)] +60}:6 =14
72-2x[36-4x(9:a)] +60 =14x6
72-2x[36-4x(9:a)] +60 =84
72-2x[36-4x(9:a)] =84-60
72-2x[36-4x(9:a)] =24
2x[36-4x(9:a)] =72-24
2x[36-4x(9:a)] =48
36-4x(9:a)=48:2
36-4x(9:a)=24
4x(9:a)=36-24
4x(9:a)=12
9:a=12:4
9:a=3
a=9:3
a=3