120 - y = 20 . b + 25 = 100. 16 - a = 4 . c - 3 = 13 . 15 + x = 30 . 60 - c = 50 . 17 - a = 9 . b - 78 = 0 . x + 70 = 100. y - 8 = 15 . 100 - c = 60 . b - 6 = 19.
120-у=20 у=120-20 у=100 b+25=100 b=100-25 b=75 16-a=4 a=16-4 a=12 c-3=13 c=13+3 c=16 15+x=30 x=30-15 x=15 60-c=50 c=60-50 c=10 17-a=9 a=17-9 a=8 b-78=0 b=78-0 b=78 x+70=100 x=100-70 x=30 y-8=15 y=15+8 y=23 100-c=60 c=100-60 c=40 b-6=19 b=19+6 b=25