what does the theta sign and red arrow symbolize?

the question:

http://img148.imageshack.us/img148/4668/theta1je0.jpg

my work:

http://img148.imageshack.us/img148/6446/theta2xr6.jpg

i don't know if this is correct. as you can see, i used the pythgorean thm to find the hypotenuse (5). then using SOHCAHTOA, i found the answers? correct or do they have to be in decimal form since it says exact values?