Can somebody help me understand this simple subtraction? I posted the picture in the replies. -1 - 1/9. Although the work is shown, I want a better explanation on how we got -9/9.

Question

starfireandrobin · Answer

attachment

misssmartiez · Answer

For one, before we do anything, we usually make the whole number into a fraction.


Like, 

3 -> 3/1

or

4 -> 4/1

misssmartiez · Answer

Two, before we do the operation, we need to make sure the denominators are the same. By doing that,|dw:1473962205181:dw|


Since the LCD is 9, we simply x 1 by 9 and leave the already nine alone.