Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Bài làm
a) ( -6 - 2 ) . ( - 6 + 20 )
= 12 . ( -120 )
= -1440
b)đề bài k rõ. Đóng Đóng mở ngoặc lung tung.
c) ( -5 + 9 ) . ( -4 )
= 4 . ( -4 )
= -16
d) 72 : ( -6 . 2 + 4 )
= 72 : ( -12 + 4 )
= 72 : ( -8 )
= ( -9 )
e) -3 . 7 - 4 . ( -5 ) + 1
= -21 + 20 + 1
= 0
f) 18 - 10 : ( 2 ) - 7
= 18 - 5 - 7
= 6
g) 15 : ( -5 ) . ( -3 ) - 8
= 9 - 8
= 1
h) ( 6 . 8 - 10 : 5 ) + 3( -7 )
= ( 48 - 2 ) - 21
= 46 - 21
= 25
# Hok tốt #
a/ \(-3\left(x-5\right)+6\left(x-2\right)=9\)
\(\Rightarrow-3x-\left(-3.5\right)+6x-\left(6.2\right)=9\)
\(\Rightarrow-3x+15+6x-12=9\)
\(\Rightarrow-3x+6x=9+12-15\)
\(\Rightarrow3x=6\)
\(\Rightarrow x=2\)
b/ \(4x-5\left(-3+x\right)=7\)
\(\Rightarrow4x-5.\left(-3\right)-5x=7\)
\(\Rightarrow4x+15-5x=7\)
\(\Rightarrow4x-5x=7-15\)
\(\Rightarrow-1x=-8\)
\(\Rightarrow x=8\)
c/ \(5\left(x-7\right)+10\left(3-x\right)=20\)
\(\Rightarrow5x-5.7+10.3-10x=20\)
\(\Rightarrow5x-35+30-10=20\)
\(\Rightarrow5x-10x=20-30+35\)
\(\Rightarrow-5x=25\)
\(\Rightarrow x=-5\)
d/ \(-4\left(x+1\right)+8\left(x-3\right)=24\)
\(\Rightarrow-4x-4.1+8x-8.6=3=24\)
\(\Rightarrow-4x-4+8x-24=24\)
\(\Rightarrow-4x+8x=24+24+4\)
\(\Rightarrow4x=52\)
\(\Rightarrow x=13\)
a) -3(x-5)+6(x-2)=9
<=>-3x+15+6x-12-9=0
<=>3x=6
<=>x=2
Vậy x=2
a, \(\frac{3}{5}-\left(-\frac{7}{10}\right)-\frac{13}{20}=\frac{3}{5}+\frac{7}{10}-\frac{13}{20}=\frac{12}{20}+\frac{14}{20}-\frac{13}{20}=\frac{13}{20}\)
b, \(\frac{3}{4}+\frac{-1}{3}-\frac{5}{18}=\frac{27}{36}+\frac{-12}{36}-\frac{10}{36}=\frac{5}{36}\)
c, \(\frac{3}{14}-\frac{5}{-8}+\frac{-1}{2}=\frac{12}{56}+\frac{35}{56}+\frac{-28}{56}=\frac{19}{56}\)
d, \(\frac{1}{2}+\frac{1}{-3}+\frac{1}{4}-\left(-\frac{1}{6}\right)=\frac{1}{2}+\frac{-1}{3}+\frac{1}{4}+\frac{1}{6}=\frac{6}{12}+\frac{-4}{12}+\frac{3}{12}+\frac{2}{12}=\frac{7}{12}\)
đ, \(\frac{19}{24}-\frac{1}{2}-\frac{1}{3}-\frac{7}{24}=\frac{19}{24}-\frac{12}{24}-\frac{8}{24}-\frac{7}{24}=-\frac{8}{24}=-\frac{1}{3}\)
g, \(-\frac{1}{3}+\frac{1}{2}-\frac{5}{6}=-\frac{2}{6}+\frac{3}{6}-\frac{5}{6}=-\frac{4}{6}=\frac{-2}{3}\)
e, \(\frac{4}{-9}+\frac{8}{5}+\frac{-5}{9}-\frac{2}{11}+\frac{7}{15}=\frac{-220}{495}+\frac{792}{495}+\frac{-275}{495}-\frac{90}{495}+\frac{231}{495}=\frac{438}{495}=\frac{146}{165}\)
ê, \(\frac{7}{11}-\left(\frac{3}{5}+\frac{7}{11}\right)=\frac{7}{11}-\frac{3}{5}-\frac{7}{11}=\left(\frac{7}{11}-\frac{7}{11}\right)-\frac{3}{5}=0-\frac{3}{5}=-\frac{3}{5}\)
Dài quá không nhanh được @@
a) -3/7-1/2
= -6/14 - 7/14
= -6/14 + -7/14 = -13/14
b) 9/15 - -1/4
= 36/60 - -15/60 = 51/60