(IMAGE ATTACHED)Y'all please help, I need this done by tomorrow, all these need to be done in substitution, if you can only solve one that's ok, I just need the work to be shown. Thank you so much! :)

Answer:
x=4 and y=7
Step-by-step explanation:
For question 9, it's difficult to explain, so here's an image of what you're supposed to do (: