I'm having trouble with math in my math book and it says express each number in scientific notification i don't know how to do that

When doing scientific notation decimal points are always placed at the end of the number if not already showing. if there's one number on the left is what your trying to get rid of.
** If the number is greater than one you move right is the positive number
** If the number is less than one move to the left is negative
IN THE EXPONENTS

5.5 x 10^4
you would move the decimal to the right 4 times
if you have a negative number on the exponent
12 x 10^-3 you would move it to the left 3 times to the left
I Hope this helped