32.1=a-21.8

5 answers

Add 21.8 to both sides of the equation.
24.8
32.1 + 21.8 doesn't equal 24.8

Please try again.
53.9
Right.

a = 51.9

Let's prove it by substituting 51.9 for a in your original equation.

32.1=a-21.8

32.1 = 53.9 - 21.8

Yep. You're right! :-)