Question

3 less than a number h is -12

Answer 1

Your equation would be h-3=-12
To solve this all you need to do is add 3 to both sides

h-3=-12
+3 +3
————
h=-9

So the equation is h-3=-12 and h would equal -9

Answer 2

I believe your equation would be ( H - 3 = -12 )