Answer:
38
Step-by-step explanation:
 
        
                    
             
        
        
        
All sides are equal in an equilateral triangle and the perpendicular bisects the side too.
so BC will be bisected and the segments be 5 each.
you can use Pythagoras theorem to find the altitude length, hypotenuse will be one side of the triangle.

$h^2=100-25=75$
$h=\sqrt{75}=5\sqrt3$
 
        
             
        
        
        
<span>you need to set up the equations solve for x or y. and substitute. I can give you the starting equations, but i cant find the answer and I don't remember how to do all the steps, but the first two equations (the ones you use to solve for x or y to use to solve for a number to subsitute. x-12=y y-14=3x and there should be one more for that they met two years ago.</span>