Toán Lớp 6: Bài 1. Tìm x, biết : A, 541 + (218 – x) = 735 b, 96 – 3(x + 1) = 42 c, ( x – 47) – 115 = 0

Question

Toán Lớp 6:  Bài 1. Tìm x, biết : A, 541 + (218 – x) = 735                          b, 96 – 3(x + 1) = 42  c, ( x – 47) – 115 = 0                                d, (x – 36) : 18 = 12  e, ( 7. x – 15 ) : 3 = 2                                f, 44 + 7. x = 100 g, 88 – 3. (7 + x) = 64                               h, 315 – (5x + 80) = 155

tuyetnhungthu · Answer

a) 541 + ( 218 - x) = 735   => 218 - x = 735 - 541 = 694   => x = 218 - 694 = -476   b) 96 - 3( x + 1) = 42   => 3(x + 1) = 96 - 42 = 54   => x + 1 = 54 : 3 = 18   => x = 17   c) ( x - 47) - 115 = 0   => x - 47 = 0 + 115 = 115   => x = 115 + 47 = 162   d)  ( x - 36) : 18 = 12   => x - 36 = 216   => x = 216 + 36 = 252   e) ( 7.x - 15) : 3 = 2   => 7x - 15 = 6   => 7x = 6 + 15 = 21   => x = 21 : 7 = 3   f) 44 + 7.x = 100   => 7x = 56   => x = 56 : 7 = 8   g) 88 - 3.( 7 + x) = 68   => 3.( 7  +x) = 88 - 64 = 24   => 7 + x = 24 : 3 = 8   => x = 8 - 7 = 1   h) 315 - ( 5x + 80) = 155   => 5x + 80 = 315 - 55 = 260   => 5x = 260 - 80 = 180   => x = 180 : 5 = 36