55 x 5 = ?
a) x/14 - 1/7 = -3/4
b) x -1/8 =5/8
c) 1/5 + 1/11 < x/55 < 2/5 + 1/55 mà x thuộc z
a) Ta có: \(\dfrac{x}{14}-\dfrac{1}{7}=\dfrac{-3}{4}\)
\(\Leftrightarrow\dfrac{x}{14}=\dfrac{-3}{4}+\dfrac{1}{7}=\dfrac{-21}{28}+\dfrac{4}{28}=\dfrac{-17}{28}\)
hay \(x=\dfrac{-17\cdot14}{28}=\dfrac{-17}{2}\)
Vậy: \(x=-\dfrac{17}{2}\)
\(a)\dfrac{x}{14}-\dfrac{1}{7}=\dfrac{-3}{4}\)
\(\dfrac{x}{14}=\dfrac{-3}{4}+\dfrac{1}{7}\)
\(\dfrac{x}{14}= \dfrac{-17}{28}\)
\(x=\dfrac{14.(-17)}{28}\)
\(x=\dfrac{-17}{2}\)
\(b)x-\dfrac{1}{8}=\dfrac{5}{8}\)
\(x=\dfrac{5}{8}+\dfrac{1}{8}\)
\(x=\dfrac{6}{8}=\dfrac{3}{4}\)
\(c)\dfrac{1}{5}+\dfrac{1}{11}<\dfrac{x}{55}<\dfrac{2}{5}+\dfrac{1}{55}(xthuộc Z )\)
\(\Rightarrow \dfrac{11}{55}+\dfrac{5}{55}<\dfrac{x}{55}<\dfrac{22}{55}+\dfrac{1}{55} \)
\(\Rightarrow \dfrac{16}{55}<\dfrac{x}{55}<\dfrac{23}{55}\)
\(\Rightarrow 21< x < 23\)
\(\Rightarrow x=22\)
x=44444444444444444444444124
1/5+2/11<x/55<2/5+1/55
1/5 + 2/11 < x/55 < 2/5 + 1/55
=> 11/55 + 10/55 < x/55 < 22/55 + 1/55
=> 21/55 < x/55 < 23/55
=> 21 < x < 23
=> x = 22
22(x+32)-5=55
155-10(x+1)=55
5.22+(x+3)=52
53-5(4+x)=15
a/ 22(x + 32) - 5 = 55 b/ 155 - 10(x+1) = 55
4(x + 32) = 60 10(x + 1) = 100
x + 32 = 60 : 4 x + 1 = 10
x + 32 = 15 x = 10 - 1
x = 15 - 32 x = 9
x = - 17
c/ 5. 22 + (x+3) = 52 53 - 5 (4 + x) = 15
20 + (x+3) = 25 125 - 5(4 +x) = 15
x+ 3 = 5 5(4 + x) = 110
x = 5-3 4 + x= 110 : 2
x = 2 4 + x = 55
x = 51
ủng hộ mk nha !!!! ^_^
mọi người giúp tôi nhé!
9.1:Chọn(C)
9.2:a)4x mũ 3=47-15=32
X mũ 3=32:4=8=2 mũ 3
X=3,..
9.3:Chẳng hạn:5+55:55=6;(55+5):(5+5)=6
5 x 5 + 5 x 55 = ?
5 x 5 + 5 x 55
= 5 x (5 + 55)
= 5 x 60
= 300
Tìm x thuộc Z :
a/1/5+2/11<x/55<2/5+1/55
b/x/21=4/7+(-7)/3
= 11/55+ 10/55<x/55<2/5+1/55
=2/5<x/55<23/55
=22/55<x/55<23/55
=> x thuộc rỗng
x/21=4/7+(-7)/3
= x/21=12/21+(-49)/21
= x/21=-37/21
=> x = -37
a)x-17/36=15/16.27/4
b) |x-2/7|+9/14.3/4=1
c)1/5+2/11<x/55<2/5+4/55 (x thuộc Z)
tìm x : 5^x + 2* 5^x+1 = 55
Bài 1: Tính hợp lý
1) - 5 x ( 37 - 17 ) + 23 x ( - 13 - 17 )
2) - 37 x ( 55 - 23 ) + 55 x ( 23 - 37 )