3(3d-1)+7(2d+1)приd= 2 4/23
9d-3+14d+7=23d+4 d=2 4/23 23*50/23+4=50+4=54
1) 9d-3+14d+7=23d+4 2) 23×2 4\23 +4= 23\1 ×50\23 +4= 50+4=54