To write something in rational form means to write it as a fraction. If you are given a negative number in the form of a fraction, it is already in rational form.
If you are given a decimal and wish to turn it into a fraction, just use 10, 100, etc as the denominator. In the case of a repeating decimal there is a method but that's another question!
-12/1
-0.0012 is a fraction. It is a fraction in decimal form rather than in the form of a ratio. However, that does not stop it being a fraction. Its equivalent, in rational form, is -12/10000. You can simplify this rational fraction if you require.
-0.4 is a fraction. It is a fraction in decimal form rather than in the form of a ratio. However, that does not stop it being a fraction. Its equivalent, in rational form, is -4/10. You can simplify this rational fraction if you require.
It is a rational number because it can be expressed as a fraction in the form of -17/1
31.456 is a fraction. It is a fraction in decimal form rather than in the form of a ratio. However, that does not stop it being a fraction. Its equivalent, in rational form, is 31456/1000. You can simplify this rational fraction if required.
It is a rational number because it can be expressed as an improper fraction in the form of -80/1
-19 is a rational number, since it can be expressed in fraction form (-19/1).
Because it can be expressed as an improper fraction in the form of -3/1 and so therefore it is a rational number
-0.25 is a fraction. It is a fraction in decimal form rather than in the form of a ratio. However, that does not stop it being a fraction. And, since it is a decimal fraction, there is not another simpler decimal form. Its equivalent, in rational form, is -25/100. You can simplify this rational fraction if you so wish.
-7 is a rational number because it can be expressed as a fraction in the form of -7/1
-0.92 is a fraction. It is a fraction in decimal form rather than in the form of a ratio. However, that does not stop it being a fraction. Its rational equivalent is -92/100 which can be simplified.
8.33 is a fraction. It is a fraction in decimal form rather than in the form of a ratio. However, that does not stop it being a fraction. Its rational equivalent is 833/100 which cannot be simplified.