\(13^2+\left(25x-4^2\right):17=171\)
\(\Leftrightarrow\left(25x-4^2\right):17=171-169\)
\(\Leftrightarrow\left(25x-4^2\right):17=2\)
\(\Leftrightarrow25x-16=34\Leftrightarrow25x=50\Leftrightarrow x=2\)
Tính tổng A= 1- 5/6 +7/12 - 9/20 + 11/30 - 13/42 + 15/56 - 17/72 + 19/90 - 21/110 + 23/132 - 25/156
A=\(1-\frac{5}{6}+\frac{7}{12}-\frac{9}{20}+\frac{11}{30}-\frac{13}{42}+\frac{15}{56}-\frac{17}{72}+\frac{19}{90}-\frac{21}{110}+\frac{23}{132}-\frac{25}{156}\)\(\frac{25}{156}\)
Giups mình nha !!!
Tìm x biết:
a)-2x-17=-11
b)15-(7-2x)=-11-(-25)
c)43-(x+17)=-17-(-25)
d)-42/x/=-15
e)/x-2/-(-13)=17
g)-11</x/<3
tính : a, 1/30 +1/42 +1/56 +1/17 +1/90 +1/110+1/132 . b, -15,5.20,8+3,5.9,2-15,5.9,3+3,5.20,8
quy đồng mẫu các ps sau:
a) 17/20 ; 13/15 và 41/60
b)25/75 ; 17/34 và 121/132
[x cộng 32 ] - 17 .2 = 42
575- [6x cộng 70 ] =25
315 cộng [ 125 -x] = 435
[x -105] chia 21 = 15
[ 61 cộng [ 51 -x ] . 17 = 1785
1.
a) 2x + 5 = 34 : 32
b) ( 3x - 24 ) . 73 = 2.74
c) [ 3 . ( 42 - x ) + 15 = 23 . 3
d) 126 + ( 132 - x ) = 300
2.
a) 120 - ( x + 55 ) = 60
b) ( 7x - 11)3 = 25 .52 + 200
c) 2x + 2x+4 = 544
3.
a) 10 + 2x = 49 : 47
b) 70 - 5 ( x - 3 ) = 45
c) 4 + 95 : x = 143 : 142 - 23
bài 1:
a) 10\17+5\-13-11\25+7\17-8\13
b) 0,3-93\7-70%0-4\7
c)1\8+1\24+1\48+...+1\2400
d) 3\41-12\17+33\49
-----------------------------
12\41-48\17+132\49
Thực hiện phép tính: (Tính nhanh nếu có thế)
1) 347.222-222.(216+184):8
2) 132-[116-(132-128)22]
3) 16:{400:[200-(37+46.3)]}
4) {184:[96-124:31]-2}.3651
5) ) 46 – [ (16 + 71 . 4 ) : 15 ]} – 2
6) 33.18 + 72 .42 – 41 .18
7)( 56 . 46 – 25 . 23 ) : 23
8) ( 28 . 54 + 56 . 36 ) : 21 : 2
9) ( 76 . 34 – 19 . 64 ) : ( 38 . 9 )
10) ( 2+ 4 + 6 + ….. + 100 ) . ( 36 . 333 – 108 . 111)
11) ( 5 . 411- 3 .165 ): 410
12) 7256.4375−725/3650+4375.7255
