Question

use the pyramid to complete parts (a) through (f) below.
a. what is the intersection of $overline{ab}$ and $overline{ad}$?
a. $varnothing$
b. point e
c. point b
d. point a
b. what is the intersection of planes abe, cde, and abc?
a. the line through $varnothing$ and point a
b. point c
c. point b
d. $varnothing$
e. point a
f. the line through $varnothing$ and point b

Explanation:

Step1: Recall line - intersection concept

Two lines that share a common starting - point intersect at that starting - point. $\overline{AB}$ and $\overline{AD}$ both start from point A.

Step2: Recall plane - intersection concept

Planes ABE, CDE, and ABC do not have a common intersection point. They are non - concurrent planes, so their intersection is the empty set $\varnothing$.

Answer:

a. D. Point A
b. D. $\varnothing$