2х^2 + 2х + х + 1 = 0
2х^2 + 3х + 1 = 0
D = 3^2 - 4 × 1 × 2 = 9 - 8 = 1
√1 = 1
Х1 = -3 - 1 = -4 = -2
2 × 1 2
Х2 = -3 + 1 = -2 = -1
2 × 1 2
Х1 = -2 Х2 = -1
3/15+6=3/15+5 15/15=5 18/15= 6 1/5
a) 7- 4 5\9 = 6 9\9 -41/9 = 63/9-41-9 = 63-41/9 = 22/9 = 2 4/9
б) 4 3/10 + 1 5/12 = 43/10 + 17/12 = 258 + 85/60 = 343/60 = 5 43/60
в) 6 15/21 + 2 9/14 = 141/21 + 37/14 = 282+111/42=393/42= 9 15/42
г) 5 1/6 - 3 3/4 = 31/6 - 15/4 = 62 - 45 /12 = 17/12 = 1 5/12
1) 120 - 40 = 80 км осталось
2) 120 - 60 = 60 км осталось
3) 120 - 80 = 40 КМ Осталось