Question

Bài 6: Tìm x :

a, (2x+1) :7=2^2+3^2 

              

Answer 1

\(\left(2x+1\right):7=2^2+3^2\)

\(\Rightarrow\left(2x+1\right):7=4+9=13\)

\(\Rightarrow2x+1=13.7=91\Rightarrow2x=91-1=90\)

\(\Rightarrow x=90:2=45\)

Answer 2

\(\Leftrightarrow2x+1=13\cdot7=91\\ \Leftrightarrow x=45\)