Question

[x-21]x13=39

Answer 1

\(\left[x-21\right]\times3=39\)

\(x-21=39:3\)

\(x-21=13\)

\(x=13+21\)

\(x=34\)

__CHÚC BN HOK TỐT__

Answer 2

x-21=39:13

x-21=3

x=3+21

x=24

Answer 3

\(\left|x-21\right|\times13=39\)

\(\Rightarrow\left|x-21\right|=39:13=3\)

\(\Rightarrow x-21=\orbr{\begin{cases}3\\-3\end{cases}}\)

\(\Rightarrow x=\orbr{\begin{cases}24\\18\end{cases}}\)

Answer 4

[x-21]x13=39

[x-21]=39:13

x-21=3

x= 3+21

=24