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.

$h^2=100-25=75$
$h=\sqrt{75}=5\sqrt3$
Answer:
C. 
D. 
Step-by-step explanation:
C. 



D. 




Answer:
D
Step-by-step explanation:

Answer:
x=31/25
Step-by-step explanation:
3x+4/5=7-2x
Multiply through by 5
5(3x+4/5)=5(7-2x)
15x+4=35-10x
Collecting like terms
15x+10x=35-4
25x=31
x=31/25
Answer:
its would prob be 100 / 4
Step-by-step explanation: