a: \(\Leftrightarrow\dfrac{x-51}{9}-1+\dfrac{x-52}{8}-1=\dfrac{x-53}{7}-1+\dfrac{x-54}{6}-1\)
=>x-60=0
hay x=60
b: \(\Leftrightarrow\left(x-2\right)^2-3\left(x+2\right)=x-14\)
\(\Leftrightarrow x^2-4x+4-3x-6-x+14=0\)
\(\Leftrightarrow x^2-8x+12=0\)
=>(x-2)(x-6)=0
=>x=2(loại) hoặc x=6(nhận)