Answer:
24
Step-by-step explanation:
Answer: 6x+3y
Step-by-step explanation:
3x+3(x+y)= 3x+3x+3y=6x+3y
AB^2 + BC^2 = AC^2
AB^2 + 6^2 = square root 117^2
AB^2 + 36 = 117
Now subtract 117 from both sides
AB^2 = 81
AB = square root 81 = 9

Therefore AB is 9 cms.
7x+(x+20)=180
Just simplify. Hope this helped:)