we have the equation
72 = 11.5 + x + 22.5
solve for x
that means
isolate the variable x
so
step 1
Combine like terms right side
72=x+34
step 2
subtract 34 both sides
72-34=x+34-34
Combine like terms
38=x
therefore
x=38
Check the solution
substitute the value of x in the original expression
72 = 11.5 + 38 + 22.5
Combine like terms
72=34+38
72=72 -----> is true
that means -----> the solution is correct