It's an isosceles triangle, so the angles at the base are congruent:

The triangle XYW is a rectangular triangle.
We know that the sum of the measures of angles in a triangle is 180°.
Therefore we have the equation:

Answer: 73
the correct question is
The midpoint of kl is m(–8, 1). one endpoint is k(–6, 5). find the coordinates of the other endpoint l.
we know that
the formula of midpoint is
Xm=(x1+x2)/2----> 2*Xm=x1+x2------> x2=2*Xm-x1
Ym=(y1+y2)/2----> 2*Ym=y1+y2------> y2=2*Ym-y1
let
(x1,y1)-------> (–6, 5).
(Xm,Ym)-----> (-8,1)
find (x2,y2)
x2=2*Xm-x1-----> 2*(-8)-(-6)----> -10
y2=2*Ym-y1----> 2*(1)-5-----> -3
the point l is (-10,-3)
Answer:
AN = 16 units
Step-by-step explanation:
So we can use the fact that 
- Since this is an isosceles triangle, segments FO and FR are both equal to 7
Manipulating the equation above to solve for AN we have 
- Substituting in the known values we have

Well, basically there are
acute angle, right angle, obtuse angle ..
and also we use concurrent angles, corresponding angles, alternate angles, vertically opposite angles,..
..hope it helped a bit