Answer:
43/156
Step-by-step explanation:
[tex]\frac{-5}{12} --\frac{9}{13} = \frac{-5}{12} +\frac{9}{13}[/tex] because subtracting a negative number is the same thing as adding the positive of that number. next you cross multiply. This means multiply the top of the first by the bottom of the second and the bottom of the first with the top of the second and multiply the denominators together.
This gives you [tex]-\frac{5x13}{12x13} +\frac{9*12}{12*13}[/tex]. Then you can combine them into [tex]\frac{-5x13+9x12}{12x13}[/tex]. Then just simplify to [tex]\frac{43}{156}[/tex]!
