Question

Помогите!!!
(Х -13) + х + х = 50

Answer 1

x-13+2x=50
3x=63
x=63/3
x=21

Answer 2

(х-13)+х+х=50
х-13+х+х=50
х+х+х=50+13
3х=63
х=63:3
х=21