Yes it is. Input the numbers into the pythagorean theorem,

and if they equal each other it is a right triangle.
Zero.
Anything times zero is zero.
-20 * -10 = 200
200 * -1 = -200
-200 * 0 = 0
Answer:
an acute triangle
Explanation:
All of the angles are less than 90 degrees, which is an acute triangle.
5x10^9
Just find out how many zeros there are
Answer:
( -4, 11 ]
Step-by-step explanation: