Hey there!
Firstly, you need combine your like terms

stays the SAME 

- Combine the negative and the plus and make a negative symbol

Good luck on your assignment and enjoy your day!
~
Answer:
10^2
Step-by-step explanation:
My understanding is that the 2 angles add up to 180 degrees, so 9x+9y-54=180. Also, 9x=90 and 9y-54=90. 9x=90, so x=10. 9y=90+54. 9y=144. y=16.
Answer:
D - 9x^(2)+2x-5
Step-by-step explanation: