In the accompanying diagram, line BD bisects acute angle ABC and line AD is parallel to line BC. What kind of triangle must triangle ABD be?

  isosceles

Step-by-step explanation:

With AD║BC, ∠ADB ≅∠DBC. The angle bisection also ensures that ∠ABD≅∠DBC. Hence the two angles ABD and ADB must be congruent to each other.

A triangle with two congruent internal angles is an isosceles triangle.

answer: expected value of x = 1.0

step-by-step explanation:

p(x=0) = 0.25

p(x=1) = 0.50

p(x=2) = 0.25

expected value for x = 0×0.25 + 1×0.5 + 2×0.25 = 1.0

its 50 miles away from the starting point