12-h equals -h plus 3

Answer 1

15

Answer 2

12 - h = -h + 3. Rewrite this.

12 - h = 3 - h Subtract 3 from both sides.

9 - h = -h Multiply through by (-1) to get a positive h

-9 + h = h

From this you can see that there is no number that you can subtract 9 from to get the same number. Answer is {} ■