Răspuns :
800:[425-13x(48:4)-(89+Ax4)]=10
425-13x(48:4)-(89+Ax4)=800:10
425-13x12-(89+Ax4)=80
425-156 - (89+Ax4)=80
269 - (89+Ax4)=80
89+Ax4 = 269-80
89+Ax4 = 189
Ax4 = 189-89
Ax4 = 100
A=100:4
A=25
425-13x(48:4)-(89+Ax4)=800:10
425-13x12-(89+Ax4)=80
425-156 - (89+Ax4)=80
269 - (89+Ax4)=80
89+Ax4 = 269-80
89+Ax4 = 189
Ax4 = 189-89
Ax4 = 100
A=100:4
A=25