43.(x-19)=86

x-19=2

x=21

\(43\times\left(x-19\right)=86\)

\(x-19=86\div43\)

\(x-19=2\)

\(x=2+19\)

\(x=21\)

@#$%^&* !

a) (x – 35).35 = 35 ó x – 35 = 1 ó x = 36

b) 43.(x – 19) = 86 ó x – 19 = 2 ó x = 21

c) (x + 7).34 = 2.34 ó x + 7 = 2

Điều này không xảy ra khi x là số tự nhiên. Vậy không có giá trị nào của x thỏa mãn

Ta có

kết quả là:

x = 0

x = -5

x = 21

nha bn

45 . ( 2.x - 4 ) . 13 = 0

45 . 13 . ( 2.x - 4 ) = 0

585 . ( 2.x - 4 ) = 0

( 2.x - 4 ) = 0 : 585

 2.x - 4  = 0

2.x = 0 + 4

2.x = 4

x = 4 : 2

x = 2

( x + 7 ) . 35 = 2.35

 x + 7  = ( 2 . 35 ) : 35

x + 7 = 35

x = 35 - 7

x = 28

43 . ( x - 19 ) = 86

x - 19 = 86 : 43

x - 19 = 2

x = 2 + 19

x = 21

\(a,86-\left(86+x\right)=10\\ \Rightarrow86+x=76\\ \Rightarrow x=10\\ b,10-x=7-\left(-8\right)\\ \Rightarrow10-x=15\\ \Rightarrow x=-5\\ c,\left(-24+x\right)-43=15\\ \Rightarrow x-24=58\\ \Rightarrow x=82\)

9: \(=\dfrac{47}{51}\cdot\dfrac{17}{94}-\dfrac{47}{51}\cdot\dfrac{53}{91}-\dfrac{53}{91}\cdot\dfrac{91}{53}+\dfrac{53}{91}\cdot\dfrac{47}{51}\)

\(=\dfrac{1}{6}-1=-\dfrac{5}{6}\)

10: \(=\dfrac{13}{19}\cdot\dfrac{19}{26}-\dfrac{13}{19}\cdot\dfrac{71}{43}+\dfrac{71}{43}\cdot\dfrac{13}{19}-\dfrac{71}{43}\cdot\dfrac{86}{71}\)

\(=\dfrac{1}{2}-2=-\dfrac{3}{2}\)

bạn giải chi tiết đi

Thôi, để mk giải chi tiết cho, không lại bảo mk lười:

A=\(\dfrac{18}{26}+\dfrac{-5}{27}+\dfrac{-22}{86}+\dfrac{12}{39}+\dfrac{-32}{43}\)

A=\(\dfrac{9}{13}+\dfrac{-5}{27}+\dfrac{-11}{43}+\dfrac{4}{13}+\dfrac{-32}{43}\)

A=\(\left(\dfrac{9}{13}+\dfrac{4}{13}\right)+\left(\dfrac{-11}{43}+\dfrac{-32}{43}\right)+\dfrac{-5}{27}\)

A= 1+(-1)+\(\dfrac{-5}{27}\)

A=0+\(\dfrac{-5}{27}\)

A=\(\dfrac{-5}{27}\)

B=\(\dfrac{-10}{12}+\dfrac{8}{15}+\dfrac{-19}{56}+\dfrac{-3}{18}+\dfrac{28}{60}\)

B=\(\dfrac{-5}{6}+\dfrac{8}{15}+\dfrac{-19}{56}+\dfrac{-1}{6}+\dfrac{7}{15}\)

B=\(\left(\dfrac{-5}{6}+\dfrac{-1}{6}\right)+\left(\dfrac{8}{15}+\dfrac{7}{15}\right)+\dfrac{-19}{56}\)

B= -1+1+\(\dfrac{-19}{56}\)

B=0+\(\dfrac{-19}{56}\)

B=\(\dfrac{-19}{56}\)

Ôi mỏi quá! Chúc bạn học tốt !

Help!

A = \(\dfrac{18}{26}\) + (-\(\dfrac{5}{27}\)) + (-\(\dfrac{22}{86}\)) + \(\dfrac{12}{39}\) - \(\dfrac{32}{43}\)

A = \(\dfrac{9}{13}\) - \(\dfrac{5}{27}\) -  \(\dfrac{11}{43}\) + \(\dfrac{4}{13}\) - \(\dfrac{32}{43}\)

A = (\(\dfrac{9}{13}\) + \(\dfrac{4}{13}\)) - (\(\dfrac{11}{43}\) + \(\dfrac{32}{43}\)) - \(\dfrac{5}{27}\)

A = \(\dfrac{13}{13}\) - \(\dfrac{43}{43}\) - \(\dfrac{5}{27}\)

A = 1 - 1 - \(\dfrac{5}{27}\)

A = 0 - \(\dfrac{5}{27}\)

A = - \(\dfrac{5}{27}\)