Y-45=9. 78-x=39. 26+a=40

Question

Y-45=9. 78-x=39. 26+a=40

Answer 1

Y=45+9=54
x=78-39=39
a=40-26=14

Answer 2

Y=9+45=54; -x=39-78; -x=-39; x=39; a=40-26=14