a) \(500+500+500=x\)
\(\Rightarrow1000+500=x\)
\(\Rightarrow1500=x\)
Vậy \(x=1500\)
b) \(x+x+x=15\)
\(\Rightarrow3x=15\)
\(\Rightarrow x=15:3\)
\(\Rightarrow x=5\)
Vậy \(x=5\)
c) \(50+50=x.50\)
\(\Rightarrow100=x.50\)
\(\Rightarrow x=100:50\)
\(\Rightarrow x=2\)
Vậy \(x=2\)