(8с-1)*5=235(8с-1)= 235:5(8с-1) =478с=47+1.8с=48с=48:8с=6(8*6-1)*5=235 235=2355t+30-2t=425t-2t+30=423t+30=423t=42-303t=12t=12:3t=55*5+30-2*5=42 42=42