Answer:
See explanation
Step-by-step explanation:
If 
then triangle PXY is isosceles triangle. Angles adjacent to the base XY of an isosceles triangle PXY are congruent, so
and
Angles 1 and 3 are supplementary, so
Angles 2 and 4 are supplementary, so
By substitution property,
Hence,
Consider triangles APX and BPY. In these triangles:
- given;
- given;- - proven,
so 
by ASA postulate.
Congruent triangles have congruent corresponding sides, then
Therefore, triangle APB is isosceles triangle (by definition).
Answer: 2
Step-by-step explanation:
Answer:
Parallel lines are straight lines that don't ever touch. Think of a railroad track.
Perpendicular lines are lines that meet and make a 90 degree angle
To do this, we're going to use the order of operations (PEMDAS):
P - Parentheses
E - Exponents
M - Multiplication
D - Division
A - Addition
S - Subtraction
First let's do parentheses, there isn't anythig in parentheses we need to simplify, so we can skip this step.
Next let's look for exponents. I see we have a 
so let's replace that with 
:
Now let's look for multiplcation. We know that things that are right next to eachother in parentheses represent multiplcation, so let's simply this more:
And now we're left with a simple problem we know how to solve.
Answer: 
Hope this helps!
Hm, it seems like his answer is off. The image is what I got.
