Apply the law of cosines. and solve for A

A = 79.04239272, or 79
I believe the next one would be 13.2 because if you add 8.4 to -6.4 it gets 4.8 so you just do the same thing
If u wrote 9 to the power of - 2 and x to the power of - 1 and y to the power of 0 and write the x at then end it would end up a fraction of 1/81 but I'm not sure what u want like multiply?
Answer:
5
Step-by-step explanation:
10-(2+3) = 5