1) Tim x biet :
a) 88 - 3 ( 7 + x ) = 64 b) 131 . x - 941 = 27 . 23
c) [ ( x + 32 ) - 17 ] . 2 = 42 d) [ ( x2 + 54 ) - 32 ] : 2 = 61
2) Thực hiện phép tính :
a) 31 . 65 + 31 . 35 - 500
b) 4 . 52 - 81 : 3
c) 22 . 25 . 11 + 5 . 20 . 27 + 102 . 56
d) 46 - { [ ( 16 + 71 : 4 ) : 15 ] } - 2
e) 120 - { 300 : [ 150 - ( 2. 53 - 23 . 25 ) ] }
g) ( 20 .24 + 12 .24 - 48 . 22 ) : 82
h) ( 75 . 54 + 175 . 54 ) : ( 20 . 25 .125 . 625 . 75 )
Ai nhanh thì mình tick cho nha !
1) Tim x biet :
a) 88 - 3 ( 7 + x ) = 64 b) 131 . x - 941 = 27 . 23 c) [ ( x + 32 ) - 17 ] . 2 = 42 d) [ ( x2 + 54 ) - 32 ] : 2 = 61
3(7+x)=88-64 131 . x - 941=1024 [ ( x + 32 ) - 17 ] =42:2 [ ( x2 + 54 ) - 32 ]=61x2
3(7+x)=24 131.x=1024+941 [ ( x + 32 ) - 17 ] =21 [ ( x2 + 54 ) - 32 ]=122
7+x=24:3 131.x=1965 x+32=21+17 x2 + 54 =122+32
7+x=8 x=1965:131 x+23=38 x2 + 54 =154
x=8-7 x=15 x=38-23 x2 =154-54
x=1 x=15 x2=100
x=10 hoặc x= -10
2) Thực hiện phép tính :
a) 31 . 65 + 31 . 35 - 500
= 31.(65+35)-500
=31.100-500
=3100-500
=2600
b) 4 . 52 - 81 : 3
=4.25-81:3
=100-27
=73
c) 22 . 25 . 11 + 5 . 20 . 27 + 102 . 56
=128.11+2700+5600
=1408+2700+5600
=9708