Bài 1:
a: ĐKXĐ: 2x-5>=0
=>2x>=5
=>\(x>=\dfrac{5}{2}\)
b: ĐKXĐ: -2x+4>=0
=>-2x>=-4
=>x<=2
c: ĐKXĐ: 2x+9>=0
=>2x>=-9
=>\(x>=-\dfrac{9}{2}\)
d: ĐKXĐ: 2023-x>=0
=>-x>=-2023
=>x<=2023
e: ĐKXĐ: -3x+6>=0
=>-3x>=-6
=>\(x< =\dfrac{6}{3}=2\)
f: ĐKXĐ: -4x+8>=0
=>\(-4x>=-8\)
=>\(x< =\dfrac{8}{4}=2\)
g: ĐKXĐ: -x+5>=0
=>\(-x>=-5\)
=>x<=5
h: ĐKXĐ: -4x-16>=0
=>4x+16<=0
=>4(x+4)<=0
=>x+4<=0
=>x<=-4
Bài 2:
a: ĐKXĐ: \(\dfrac{1}{3}x-1>=0\)
=>\(\dfrac{1}{3}x>=1\)
=>\(x>=1:\dfrac{1}{3}=3\)
b: ĐKXĐ: \(\dfrac{x}{2}-5>=0\)
=>\(\dfrac{x}{2}>=5\)
=>x>=10
c: ĐKXĐ: \(\dfrac{2}{3}x-1>=0\)
=>\(\dfrac{2}{3}x>=1\)
=>\(x>=1:\dfrac{2}{3}=\dfrac{3}{2}\)
d: ĐKXĐ: \(-\dfrac{1}{4}x+\dfrac{1}{3}>=0\)
=>\(-\dfrac{1}{4}x>=-\dfrac{1}{3}\)
=>\(x< =\dfrac{1}{3}:\dfrac{1}{4}=\dfrac{4}{3}\)
Bài 3:
a: ĐKXĐ: \(2-\dfrac{x}{5}>=0\)
=>\(\dfrac{x}{5}< =2\)
=>x<=10
b: ĐKXĐ: \(1-\dfrac{x}{3}>=0\)
=>\(\dfrac{x}{3}< =1\)
=>x<=3
c: ĐKXĐ: \(\dfrac{2}{3}-\dfrac{x}{-4}>=0\)
=>\(\dfrac{x}{4}+\dfrac{2}{3}>=0\)
=>\(\dfrac{3x+8}{12}>=0\)
=>3x+8>=0
=>3x>=-8
=>\(x>=-\dfrac{8}{3}\)
d: ĐKXĐ: \(6-\dfrac{-x}{5}>=0\)
=>\(\dfrac{x}{5}+6>=0\)
=>\(\dfrac{x}{5}>=-6\)
=>x>=-30
