It is always isosceles because it can be proved as follows:
The perpendicular bisector dissects the triangle into two, and it is the common side. Then each side of the bisector is 90 degrees, and the bisected to two equal sides, so the two dissected triangles are congruent, hence the original triangle is isosceles.
For this case we have the following expression:
Using the associative property we can rewrite the expression in the following way:
Finally, simplifying we have:
Answer:
Rewriting the expression we have that the result is:
d. -7
The formula of an area of a circle:

r - a radius
We have r = 14m. Substitute:

If you want an approximate area, you can accept 
Then:

28 hope this helps if it does thank me later
Answer:
1. 5.45
2. 0.94
Step-by-step explanation: