Question

Можете пожалуйста решить #2? СРОЧНО!

Answer 1

1254.
а) 8,757 - (7,8 - 1,043) = 8,757 - 6,757 = 2
б) 3,96 + (2,375 -3,96) = 3,96 + (-1,585) = 3,96 - 1,585 = 2,375
в) 3/8 + (1/8 - 3/4) = 3/8 + (- 5/8) = 3/8 - 5/8 = - 1/4
г) (2 3/7 + 1 5/9) - (1 4/7 + 5/9) = ((2 + 1) + (3/7 + 5/9)) - (11/7 + 5/9) = (3 + 62/63) - 134/63 = 3 62/63 - 134/63 = 251/63 - 134/63 = 13/7
д) - (2,77 - 7 2/9) - (0,23 - 4 7/9) = - (277/100 - 65/9) - ( 23/100 - 43/9) = - ( - 4007/900 ) - ( - 4093/900) = 4007/900 + 4093/900 = 9
е) - (5/6 + 1,37) - (-2,87- 1/3) = - (5/6 + 137/100) - ( - 287/100 - 1/3) = - 661/300 - ( - 961/300 = - 661/300 + 961/300 = 1
1255.
а) 0,2 - (x - 3,3) = 0,2 - x + 3,3 = 3,5 - x
б) y - (3,5 + y) = y - 3,5 - y = - 3,5
в) 2,9 - (x - 6,7) = 2,9 - x + 6,7 = 9,6 - x
г) 9 - (8 2/3 - x) = 9 - (26/3 - x) = 9 - 26/3 + x = 1/3 + x
д) c - (a + c) = c - a - c = - a
е) (a + b) - (b + a) = (1 - 1)(a + b) = 0(a+b) = 0
1256.
a) 8,4 - (x - 7,2) = 8,6
8,4 - x + 7,2 = 8,6
15,6 - x = 8,6
- x = 8,6 - 15,6
- x = - 7 |:(-1)
x = 7