y=(m-2)x+5
=>(m-2)x-y+5=0
\(d\left(O;d\right)=\dfrac{\left|\left(m-2\right)\cdot0+0\cdot\left(-1\right)+5\right|}{\sqrt{\left(m-2\right)^2+1}}=\dfrac{5}{\sqrt{\left(m-2\right)^2+1}}\)
Để d=3 thì \(\sqrt{\left(m-2\right)^2+1}=\dfrac{5}{3}\)
=>(m-2)^2+1=25/9
=>m-2=4/3 hoặc m-2=-4/3
=>m=10/3 hoặc m=2/3