Question

можете решить номер 8?дам 30 балов

Answer 1

1) 3×X-7800=1200
3x=1200+7800
3x=9000
x=9000÷3
x=3000
2)(y+2958)÷57=139
(y+2958)÷57×57=139×57
y+2958=7923
y=7923-2958
y=4965
3)38007÷(5000-z)=9
38007÷(5000-z)×(5000-z)=9×(5000-z)
38007=9×(5000-z)
38007÷9=(5000-z)×9÷9
4223=5000-z
z+4223=5000
z =5000-4223
z =777