Bài 13:
a: \(\frac{3x-7}{2}+\frac{x+1}{3}=-16\)
=>\(\frac{3\left(3x-7\right)+2\left(x+1\right)}{6}=-16\)
=>3(3x-7)+2(x+1)=-96
=>9x-21+2x+2=-96
=>11x-19=-96
=>11x=-96+19=-77
=>x=-7
b: \(x-\frac{x+1}{3}=\frac{2x+1}{5}\)
=>\(\frac{15x-5\left(x+1\right)}{15}=\frac{3\left(2x+1\right)}{15}\)
=>15x-5(x+1)=3(2x+1)
=>15x-5x-5=6x+3
=>10x-5=6x+3
=>4x=8
=>x=2
c: \(\frac{7-3x}{12}+\frac34=2\left(x-2\right)+\frac{5\left(5-2x\right)}{6}\)
=>\(\frac{7-3x+9}{12}=\frac{24\left(x-2\right)}{12}+\frac{10\left(5-2x\right)}{12}\)
=>-3x+16=24(x-2)+10(5-2x)
=>-3x+16=24x-48+50-20x=4x+2
=>-7x=-14
=>x=2
d: \(\frac{2x-1}{3}-\frac{5x+2}{7}=x+13\)
=>\(\frac{7\left(2x-1\right)-3\left(5x+2\right)}{21}=x+13\)
=>7(2x-1)-3(5x+2)=21(x+13)
=>21x+273=14x-7-15x-6=-x-13
=>22x=-286
=>x=-286:22=-13
e: \(\frac{3\left(x+3\right)}{4}+\frac12=\frac{5x+9}{3}-\frac{7x-9}{4}\)
=>\(\frac{9\left(x+3\right)}{12}+\frac{6}{12}=\frac{4\left(5x+9\right)-3\left(7x-9\right)}{12}\)
=>9(x+3)+6=4(5x+9)-3(7x-9)
=>9x+27+6=20x+36-21x+27
=>9x+33=-x+63
=>10x=30
=>x=3
f: \(\frac{2x-3}{3}-\frac{x-3}{6}=\frac{4x+3}{5}-17\)
=>\(\frac{10\left(2x-3\right)-5\left(x-3\right)}{30}=\frac{6\left(4x+3\right)}{30}-\frac{510}{30}\)
=>10(2x-3)-5(x-3)=6(4x+3)-510
=>20x-30-5x+15=24x+18-510
=>15x-15=24x-492
=>-9x=-492+15=-477
=>x=53
