To determine: The linear equation 1.2m−3.2−1.6 and check the solution.

Subtract 0.8 m from both sides of the equation.
${\displaystyle 1.2m-3.2-0.8m=0.8m-1.6-0.8m}$
Combine the like terms.
${\displaystyle (1.2m-0.8m)-3.2=(0.8m-0.8m)-1.6}$
${\displaystyle 0.4m-3.2=0-1.6}$
${\displaystyle 0.4m-3.2=-1.6}$
Again, add 3.2 to both sides of the equation.
${\displaystyle 0.4m-3.2+3.2=-1.6+3.2}$
Combine the like terms.
${\displaystyle 0.4m-0=-1.6+3.2}$
$0.4m=1.6$
Express rhe decimal linear equation as an equivalent linear equation without decimals.
Multiply both sides of the equation by 10.
${\displaystyle 10\left(0.4m\right)=10\left(1.6\right)}$
$4m=16$
Divide both sides of the equation by 4.
${\displaystyle \frac{4m}{4}=\frac{16}{4}}$
$m=4$
Check the solution by substituting $m=4$ in the original equation.
${\displaystyle 1.2\left(4\right)-3.2(=)0.8\left(4\right)-1.6}$
${\displaystyle 4.8-3.2=3.2-1.6v}$
$1.6=1.6$
Since $m=4$ satisfiesnthe original equation, the solution is 4.