30*(60+а)=4500 120-40/k=40 (300-n)/20=9 70*x-150=60 5600/(360/k-20)=80

30*(60+а)=4500 60+a = 150 a = 150-60 a = 90 120-40/k=40 40/k = 120-40 40/k = 80 k = 80:40 k = 1/2 (300-n)/20=9 300-n = 180 n = 300-180 n = 120 70*x-150=60 70x = 60+150 70x = 210 x = 3 5600/(360/k-20)=80 360/k-20=5600/80 360/k-20 = 70 360/k = 70+20 360/k = 90 k = 360/90 k = 4