Answer:
The length side of the triangle is 
Step-by-step explanation:
we know that
The equilateral triangle has three equal sides and three equal internal angles of measure of 60 degrees each.
Let
b------> the length side of the equilateral triangle
Applying Pythagoras theorem

Answer:
502
Step-by-step explanation
108 has the numbers 0, 1, and 8 which added together totals 9
603 has the numbers 0, 3, and 6 which added together totals 9
360 has the numbers 0, 3, and 6 which added together totals 9
502 has the numbers 0, 2, and 5 which equal 7
502 is the odd one out