c) \(53-7x=57:55\Leftrightarrow53-7x=\dfrac{57}{55}\Leftrightarrow x=\dfrac{2858}{385}.\)
c) \(53-7x=57:55\Leftrightarrow53-7x=\dfrac{57}{55}\Leftrightarrow x=\dfrac{2858}{385}.\)
a) -2x - (-17)= 9 b) 11 + (15 – x) = 1
c) 53 – 7x = 57 : 55 | d) 29 +9.x2 = 110 |
e) (2x-4).(3-x) = 0
g) 2x + 1 chia hết cho x -2 |
a) -2x - (-17)= 9 b) 11 + (15 – x) = 1
c) 53 – 7x = 57 : 55 |
b) 11 + (15 – x) = 1
d) 29 +9.x2 = 110
e) (2x-4).(3-x) = 0
g) 2x + 1 chia hết cho x -2
49-51+53-55+57-59+61
49-51+53-55+57-59+61+-63
49-51+53-55+57-59+61-63+65
bỏ ngoặc rồi tính
(57-725)-(605-53)
(55+45+15)-(15-55+45)
Tính các tổng sau
a, A = 1 + 5 3 + 5 5 + 5 7 + . . . + 5 99
b, A = 1 - 2 + 2 2 - . . . - 2 2007
c, A = 7 + 7 3 + 7 5 + 7 7 + . . . + 7 1999
Tính các tổng sau:
a) A = 1 + 5 3 + 5 5 + 5 7 + . . . + 5 99
b) A = 1 - 2 + 2 2 - . . . - 2 2007
c) A = 7 + 7 3 + 7 5 + 7 7 + . . . + 7 1999