How do you find the difference temperature that begins at 14 degrees but drops to -25 degrees by evening?

An easy way is to pretend that 25 is positive. 14+25= 39. If we know that the mathematical equation of positive+negative= negative, then we switch the 39 to -39.

Hello!

The difference means to subtract we would get what is seen below.

14--25

Subtracting means to do the opposite of something, so subtract 25 instead of adding it. When you have two subtraction signs in means to do the opposite of the opposite. As you can see it cancels out and it stays the same. If you subtract a negative number, you actually add its positive integer.

14+25
39

The difference is 39 degrees.

I hope this helps!