What MUST be true about the triangle A) the triangle is right

B) the triangle is scalene

C) the triangle is isosceles

D) the triangle is equilateral

In triangle abc segment de is parallel to the side ac . (the endpoints of segment de lie on the sides ab and bc respectively). find de, if ac=20cm, ab=17cm, and bd=11.9cm;

The product of two negative rational numbers is always zero sometimes zero never zero

Reduce fractions expressing probability to lowest terms. in 3,000 repetitions of an experiment, a random event occurred in 500 cases. the expected probability of this event is?