1:
c: \(\left(3x-1\right)\left(x+3\right)=\left(2-x\right)\left(5-3x\right)\)
=>\(3x^2+9x-x-3=10-6x-5x+3x^2\)
=>8x-3=-11x+10
=>19x=13
=>\(x=\dfrac{13}{19}\)
d: \(\left(x+1\right)\left(2x-3\right)-3\left(x-2\right)=2\left(x-1\right)^2\)
=>\(2x^2-3x+2x-3-3x+6=2\left(x^2-2x+1\right)\)
=>\(2x^2-4x+3=2x^2-4x+2\)
=>3=2(vô lý)
=>Phương trình vô nghiệm
Câu 2:
a: \(\dfrac{x}{3}-\dfrac{5x}{6}-\dfrac{15x}{12}=\dfrac{x}{4}-5\)
=>\(\dfrac{4x-10x-15x}{12}=\dfrac{3x-60}{12}\)
=>-21x=3x-60
=>-24x=-60
=>\(x=\dfrac{5}{2}\)
b: \(\dfrac{x+5}{2}+\dfrac{3-2x}{4}=x-7+\dfrac{x}{6}\)
=>\(\dfrac{6\left(x+5\right)+3\left(3-2x\right)}{12}=\dfrac{12\left(x-7\right)+2x}{12}\)
=>6x+30+9-6x=12x-84+2x
=>14x-84=39
=>14x=84+39=123
=>\(x=\dfrac{123}{14}\)
c: \(\dfrac{x+1}{35}+\dfrac{x+3}{33}=\dfrac{x+5}{31}+\dfrac{x+7}{29}\)
=>\(\dfrac{x+1}{35}+1+\dfrac{x+3}{33}+1=\dfrac{x+5}{31}+1+\dfrac{x+7}{29}+1\)
=>\(\dfrac{x+36}{35}+\dfrac{x+36}{33}=\dfrac{x+36}{31}+\dfrac{x+36}{29}\)
=>x+36=0
=>x=-36
