Question

What is the perimeter of triangle UVW

Answer 1

Count how much spaces from one point on the end of the line to the other.

Line VU has 9 units
Line VW has 12 units
Line UW has: 

a² + b² = c²
9² + 12² = c²
81 + 144 = c²
c² = 225
√c² = √225
c = 15
Line UW has: 15 units

Now add all the units together to get the perimeter:

9 + 12 + 15 = 
21 + 15 = 
36

36 is your answer

hope this helps