Question

the altitudes of a right triangle intersect
select one:
a. at one of the vertices of the triangle
b. inside the triangle
c. outside the triangle

if two straight lines intersect, the vertical angles formed are always
select one:
a. complementary
b. equal
c. supplementary

Explanation:

For the first question: In a right triangle, the two legs are also altitudes, and they intersect at the right-angle vertex. The third altitude runs from this vertex to the hypotenuse, so all three altitudes meet at the right-angle vertex.
For the second question: By the vertical angles theorem, when two straight lines intersect, the opposite (vertical) angles are congruent (equal). Complementary angles sum to 90°, supplementary to 180°, which does not apply to vertical angles.

Answer:

1. a. at one of the vertices of the triangle
2. b. equal