What is impossible to draw?
a right obtuse triangle
b right scalene triangle
c acute isosceles triangle
d obtuse scalene triangle

! im so stuck!
im pretty sure it is a though. : )

You're right! The answer is:
A) Right obtuse triangle
It is impossible to have a 180 degree angle because all three of a triangle's angles have to equal 180. If you have one angle of 180, then you would have 2 angles of 0, making a plain old straight line.