3 * x - x = 80
3 * x - x * 1 = 80
(3 - 1) * x = 80
2 * x = 80
x = 80 : 2
x = 40
3 * x - x = 80
3 * x - x * 1 = 80
(3 - 1) * x = 80
2 * x = 80
x = 80 : 2
x = 40
\(3x-x=80\)
\(=>2x=80\)
\(=>x=80:2\)
\(=>x=40\)
\(3\cdot x-x=80\)
\(\Rightarrow2x=80\)
\(\Rightarrow x=80:2\)
\(\Rightarrow x=40.\)