Question

((1700+4x)*9):47-123=777

Answer 1

((1700+4х)*9):47-123=777
(1700*9+4х*9):47-123=777
(15300+36х):47-123=777
15300+36х=(777+123)*47
15300+36х=777*47+123*47
36х=36519+5781-15300
36х=42300-15300
36х=27000
х=2700:36
х=750