Answer:
x= -5/9
That is the answer, try it.
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.

$h^2=100-25=75$
$h=\sqrt{75}=5\sqrt3$
First find the formula which is A(N)=A+(N-1)D then fill in what you know
N=term your looking for
A=first term
D= common diffrence
Once filled in you will get this 18(18)=18+(18-1)-6
then solve to get 324= -84
Your final answer is that the 18th term is -84
Hope I could help
where is the question , without question how can we find the Values
If x=2, the line is just a straight, vertical line intersecting the x-axis at 2.