Ta co :
(x.5 + 16 ) :3 =7
x .5 + 16 = 7 .3
x .5 +16 = 21
x .5 = 21 - 16
x .5 = 5
x = 5 : 5
x = 1
Vay x bang 1
ta có : x * 5 + 16 : 3 = 7
x * 5 + 16 = 7 * 3
x * 5 + 16 = 21
x * 5 = 21 - 16
x * 5 = 5
x = 5 : 5
x = 1
Ta có:
(Xx5+16):3=7
Xx5+16=7x3
Xx5+16=21
Xx5=21-16
Xx5=5
X =5:5
X =1
\(\left(x\times5+16\right)\div3=7\)
\(\left(x\times5+16\right)=7\times3\)
\(\left(x\times5+16\right)=21\)
\(x\times5=21-16\)
\(x\times5=5\)
\(x=5\div5\)
\(x=1\)