Notes – Lesson 2.3
Geometry
Name _______________________________
Use your rules of logic to draw a conclusion.
1.
If M is the midpoint of a segment, then it divides the segment into two congruent segments.
M is the midpoint of AB .
2.
If a river is more than 4000 miles long, then it is longer than the Amazon.
If a river is longer than the Amazon, then it is the longest river in the world.
3.
If a quadrilateral is a rhombus, then its diagonals are perpendicular.
Quadrilateral ABCD is a rhombus.
4.
Shannon went to the school play on either Friday or Saturday night.
She did not go to the school play on Saturday night.
5.
If an integer n is evenly divisible by 6, then n is evenly divisible by 3.
The integer 5014 is not evenly divisible by 3.
6.
If Uranium 238 decays radioactively, then it emits alpha particles.
If Uranium 238 emits alpha particles, then it eventually turns into lead.
Decide if each argument is valid or invalid.
7.
p
q
8.
r
p
q
r
p or q
9.
u
not p
not u
q
 not v
v
Decide if each argument is valid or invalid.
10.
All multiples of 20 are multiples of 5.
Sam’s locker is a multiple of five.
Therefore, Sam’s locker number is a multiple of 20.
11.
Every member of a youth hostel club likes to travel.
Samantha is not a member of a youth hostel club.
Therefore, Samantha does not like to travel.
12.
If a person wears tinted glasses, then he may be wearing a disguise.
James wears tinted glasses.
Therefore, James may be wearing a disguise.