Answer:
check the screenshot I attached:
Can't answer 1-6 cause I have no idea what you need
7) A triangle with two congruent sides is isosceles.
8)
and 
9) 
10) 
11) 
12) isosceles triangle
Answer:
2a-6=a
Step-by-step explanation:
The keyword "times" lets us know we need to multiply 2 and a and "less" shows us we need to subtract 6 from that.
We know that
m∠1 and m∠8 are alternate exterior angles
so
the answer is
the option C) m∠1 ≅ m∠8