Ta có\(\frac{x+21}{x}\times3=15+12\times6\)
=> \(\frac{x+21}{x}\times3=87\)
=> \(\frac{x+21}{x}=29\)
=> \(x+21=29\times x\)
=> \(28\times x=21\)
=> \(x=\frac{3}{4}\)
( x + 21) : X x 3=15 + 12 x 6
( x + 21) : X x 3=15 + 72
( x + 21) : X x 3=87
( x + 21) : X = 87 : 3
( x + 21) : X = 29
x + 21 = 29 x X
21 = 28 x X
28 x X = 21
=> X = 21 : 28
=> X = 3/4
bài rứa mà k biết giải ,ngu
\(\left(x+21\right):x\times3=15+12\times6\)
\(\Leftrightarrow\frac{x+21}{x}\times3=87\)
\(\Leftrightarrow\frac{x+21}{x}=29\)
\(\Leftrightarrow x+21=29\times x\)
\(\Leftrightarrow21=28\times x\)
\(\Leftrightarrow x=\frac{21}{28}=\frac{3}{4}\)
( x + 21) : X . 3=15 + 12 x 6
( x + 21) : X . 3=15 + 72
( x + 21) : X. 3=87
( x + 21) : X = 87 : 3
( x + 21) : X = 29
x + 21 = 29. X
21 = 28 . X
28 .X = 21
X = 21 : 28
X = 3/4
Vậy X=3/4
TRẺ TRÂU CHƯA TRÃI SỰ ĐỜI BÀI RỨA K BIẾT
Bài làm :
Ta có :
\(\left(x+21\right)\div x\times3=15+12\times6\)
\(\Leftrightarrow\left(x+21\right)\div x\times3=87\)
\(\Leftrightarrow x\div x+21\div x=87\div3\)
\(\Leftrightarrow1+21\div x=29\)
\(\Leftrightarrow21\div x=28\)
\(\Leftrightarrow x=\frac{21}{28}=\frac{3}{4}\)
Vậy x=3/4