Question

Help me !

Tìm x thuộc N , biết :

\(720:[41-\left(2x-5\right)]=2^3.5\)

Answer 1

\(720:\left[41-\left(2x-5\right)\right]=2^3.5\)

\(\Leftrightarrow720:\left[41-\left(2x-5\right)\right]=40\)

\(\Leftrightarrow41-\left(2x-5\right)=720:40\)

\(\Leftrightarrow41-\left(2x-5\right)=18\)

\(\Leftrightarrow2x-5=41-18\)

\(\Leftrightarrow2x-5=23\)

\(\Leftrightarrow2x=28\)

\(\Leftrightarrow x=14\)

Answer 2

Ta có :\(720:\left[41-\left(2X-5\right)\right]=2^3\cdot5\)

\(\Leftrightarrow41-\left(2X-5\right)=18\)

\(\Leftrightarrow2X-5=23\)

\(\Leftrightarrow2X=28\)

\(\Leftrightarrow X=14\)(TMĐK)

Vậy X= 14 là giá trụ cần tìm.