1) 137,1:45,7=3 ч.
2) 3*(45,7+72,3)=360 км.
1) y+ y/y-6 = y(y-6)+y/y-6
2) 2y-12/y²-25 • y(y-6)+y = 2(y-6)y(y-6+1)/(y+5)(y-5)(y-6) = 2y(y-6+1)/(y+5)(y-5) = 2y²-12y+2y/y²-25 = 2y²-10y/y²-25 = 2y/y+5
X - весь путь
20 + 20*2 +(20*2)-27 = x
x= 20 +40 +13
x = 73