(x+240)•3-360=540 867+y+9869=78000 , решу сам.

3x+720-360=540
3x=540-720+360
3x=180
x=180:3
x= 60

y=78000-867-9869
y= 67264

(x+240)*3 = 540 + 360
(x+240)*3 = 900
x+240 = 900 : 3
x+240 = 300
x = 300 - 240
x = 60

867 + y + 9869 = 78000
y = 78000 - 9869 - 867
y = 67264