The reason for this is because, it has a right angle so therefore, it already can be only B or D. However isosceles talk about having two sides of equal length. This triangle does not therefore, it cannot be B. That means it can only be D. right scalene
You immediately know that it is a obtuse because of the way it looks and the fact that there is a 130 degrees angle in the triangle. Therefore, you only have A and B and since isosceles triangles have two equal acute angles that won't work. Therefore, your only answer would be obtuse scalene.
