Explanation:
The two equations are
and 
To determine why the two equations are equivalent, let us solve the equation.
Consider solving the equation
, we get,
Adding 13 on both sides, we get,

Consider solving the equation
, we get,
Adding 37 on both sides, we get,

Thus, when solving both the equations, the value of H is equal.
Since, the value of H is equal, the equations
and
are equivalent equations.
The meaning of the solution:
A value of a variable which makes the equation true is called a solution.
Here the value of the variable H is 197. Let us substitute the value in the equations
and
to determine whether it makes the equation true.
Let us substitute
in
, we get,


Hence,
is true solution.
Also, let us substitute
in
, we get,


Hence,
is true solution.