5x + 3x + 6x = 280
14x = 280
x = 280 : 14
x = 20
Vậy x = 20
( 2x - 18 ) - 125 = 325
( 2x - 18 ) = 325 + 125
2x - 18 = 450
2x = 450 + 18
2x = 468
x = 234
Vậy x = 234
\(5x+3x+6x=280\)
\(\Rightarrow x\left(5+3+6\right)=280\)
\(\Rightarrow x.14=280\)
\(\Rightarrow x=20\)
b, \(\left(2x-18\right)-125=325\)
\(\Rightarrow2x-18=450\)
\(\Rightarrow2x=468\)
\(\Rightarrow x=234\)
\(5x+3x+6x=280\)
\(\Leftrightarrow\left(5+3+6\right)x=280\)
\(\Leftrightarrow14x=280\)
\(\Leftrightarrow x=280:14\)
\(\Leftrightarrow x=20\)
\(\left(2x-18\right)-125=325\)
\(\Leftrightarrow2x-18=325+125\)
\(\Leftrightarrow2x-18=450\)
\(\Leftrightarrow2x=450+18\)
\(\Leftrightarrow2x=468\)
\(\Leftrightarrow x=268:2\)
\(\Leftrightarrow x=234\)
5x + 3x + 6x = 280
14x = 280
x = 280 : 14
x = 20
Vậy x = 20
( 2x - 18 ) - 125 = 325
2x - 18 = 325 + 125
2x - 18 = 450
2x = 450 + 18
2x = 468
x = 468 : 2
x = 234
Vậy x = 234
=))
a )5x+3x+6x=280 b )
x(5+3+6)=280
x14=280
x=280:14
x=20
