Tìm x biết:
a. IxI + Ix+2I = 3
b. [ 12/25 . ( 0,75 + 7/4) - 1 ] x = [ 7/5 - 3/25 . ( 10,6 - 3/5 ) ]
Giúp mk vs!
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(\dfrac{1}{2}+\dfrac{3}{4}-\left(\dfrac{3}{4}-\dfrac{4}{5}\right)\)
=\(\dfrac{1}{2}+\dfrac{3}{4}-\dfrac{3}{4}+\dfrac{4}{5}\)
=\(\left(\dfrac{1}{2}+\dfrac{4}{5}\right)+\left(\dfrac{3}{4}-\dfrac{3}{4}\right)\)
=\(\left(\dfrac{5}{10}+\dfrac{8}{10}\right)+0\)
=\(\dfrac{13}{10}\)
\(-\dfrac{7}{25}.\dfrac{11}{13}+\left(-\dfrac{7}{25}\right).\dfrac{2}{13}-\dfrac{18}{25}\)
=\(-\dfrac{7}{25}.\cdot\left(\dfrac{11}{13}+\dfrac{2}{13}\right)-\dfrac{18}{25}\)
=\(-\dfrac{7}{25}.1-\dfrac{18}{25}\)
=\(-\dfrac{7}{25}-\dfrac{18}{25}\)
=\(-\dfrac{25}{25}\) = \(-1\)
a: \(x+\dfrac{3}{9}=\dfrac{7}{6}\cdot\dfrac{2}{3}\)
=>\(x+\dfrac{1}{3}=\dfrac{14}{18}=\dfrac{7}{9}\)
=>\(x=\dfrac{7}{9}-\dfrac{1}{3}=\dfrac{7}{9}-\dfrac{3}{9}=\dfrac{4}{9}\)
b: \(x-\dfrac{2}{3}=\dfrac{1}{8}:\dfrac{5}{4}\)
=>\(x-\dfrac{2}{3}=\dfrac{1}{8}\cdot\dfrac{4}{5}=\dfrac{1}{10}\)
=>\(x=\dfrac{1}{10}+\dfrac{2}{3}=\dfrac{3+20}{30}=\dfrac{23}{30}\)
a, 14 - x - 10 = -9 + 15
=> - x = 6 - 14 + 10
=> - x = 2
=> x = -2
vay_
b, |x| + 5 + 7 = 10
=> |x| = -2
=> x thuoc tap hop rong
vay_
A) 14-x-10 = ( -9) + 15
14-x-10 = 6
14-x=6 + 10
14-x = 16
x = 14 - 16
x = -2
a.
31,5 – x = (18,6 – 12,3) : 3
31,5 - x = 2,1
x = 31,5 - 2,1
x = 29,4
b.
???
\(a)\) \(\left|x\right|=\left|x+2\right|=3\)
\(\text{Trường hợp 1:}\)
\(\Leftrightarrow x+x+2=3\)
\(\Leftrightarrow2x=1\)
\(\Leftrightarrow x=\frac{1}{2}\)
\(\text{Trường hợp 2:}\)
\(\Leftrightarrow-x-x-2=3\)
\(\Leftrightarrow-2x=5\)
\(\Leftrightarrow x=-\frac{5}{2}\)
\(b)\) \([\frac{12}{25}.\left(0,75+\frac{7}{4}\right)-1].x=[\frac{7}{5}-\frac{3}{25}.\left(10,6-\frac{3}{5}\right)]\)
\(\Leftrightarrow[\frac{12}{25}.2,5-1].x=[\frac{7}{5}-\frac{3}{25}.10]\)
\(\Leftrightarrow[1,2-1].x=[\frac{7}{5}-2]\)
\(\Leftrightarrow0,2.x=-\frac{3}{5}\)
\(\Leftrightarrow x=-\frac{3}{5}:0,2\)
\(\Leftrightarrow x-3\)