Number 1 seems to right, number 3, and b) also seem to be correct, the second one y=16. For number 4 I am getting approx 9cm not 3√3 which is about 5.2, the other length for question 4 seems to be wrong also. So you need to fix numbers 2,4 and 5. Are you asked to simplify your answers? Because this is quite messy. (note I may have read some of your problems wrong because there so messy, but i think I took the correct lengths you'd given)
