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Pre-test for Geo_L_A_C Online Course
Geometry Review & Exercises
Presented by Joys Simons
Lines Introduction
Circles Introduction
Lines Questions
Circles Questions
Answers to Lines
Answers to Circles
Reminder - Lines
Reminder - Circles
Angles Introduction
Lines Quiz
Angles Questions
Angles Quiz
Answers to Angles
Circles Quiz
Reminder - Angles
Lines Q. Review
Angles Q. Review
Circles Q. Review
In geometry, a basic building block is the line, which is
understood to be a “straight” line. It is also understood that
lines are infinite in length. In the figure below, A and B are
points on line .
• What is it called? (That part of line from A to
B, including the endpoints A and B )
• Which is ? in length?
.
That part of line from A to B, including the
endpoints A and B, is called a line segment, which
is finite in length.
.
Sometimes the notation “AB” denotes line
segment AB and sometimes it denotes the length
of line segment AB. The exact meaning
of the notation can be determined from the
context.
.
Lines 1 and 2 , shown below, intersect at point
P. Whenever two lines intersect at a single
point, they form four angles.
.
• What do the opposite angles called?
• What is the sum of the measures of the four
angles?
.
Opposite angles, called vertical angles, are the same
size, i.e., have equal measure. Thus, APC and DPB have
equal measure, and APD and CPB also have equal
measure. The sum of the measures of the four angles is
360°.
An angle that measures 90 is called a right
angle, and an angle that measures 180 is called a
straight angle.
The set of all points in a plane that are a given distance r
from a fixed point O is called a circle. The point O is
called the center of the circle, and the distance r is
called the radius of the circle. Also, any line segment
connecting point O to a point on the circle is called a
radius.
.
• What is it called for any line segment that has
•
.
its endpoints on a circle, such as PQ below?
What is it called for any chord that passes
through the center of a circle?
Any line segment that has its endpoints on a
circle, such as PQ below, is called a chord. Any
chord that passes through the center of a circle
is called a diameter.
.
the diameter of a circle is always equal to twice
its radius. The distance around a circle is called its
circumference. In any circle, the ratio of the
circumference c to the diameter d is a fixed
constant, denoted by the Greek letter Л.
.
Lines l and m below are parallel. Find the values
of x and y.
A
x=57, y=138
B
X=50, y=140
C
x=55, y=145
In the figure below, AC = BC. Find the values
of x and y.
A
x=65, y=120
B
X=70. y=125
C
x=75, y=130
The figure below shows two concentric circles each with center O. If the
larger circle has radius 12 and the smaller circle has radius 8, find the
area of the shaded region.
A
The area = 78 Л
B
The area = 75 Л
C
The area = 80 Л
Back to Lines Quiz
Back to Angles Quiz
Back to Circles Quiz
Back to Lines Quiz
Back to Angles Quiz
Back to Circles Quiz
Geometry review & Exercises
Geometry Review
Lines
Angles
Circles
Geometry Exercises
Lines
Angles
Circles
Quiz & Interaction will be placed here
Lines l and m below are parallel. Find the values of x and y.
From our Lines introduction chapter, we knew when two lines are parallel,
the angles on the same side will be equal; we should also remember, the
opposite angles are equal; since the opposite angle of 57° has already
provided to us, that’s why the x = 57. On the other hand, we knew that
the straight angle = 180° and the opposite angle is 42° (It is the provided
information.) So y = 180 - 42 = 138.
Please contact me at chaosimo@msu.edu if you need help.
In the figure below, AC = BC. Find the values of x and y.
From our Angles introduction chapter, we knew that if a triangle has two sides
of equal length, then the measures of the angles opposite the two sides are
equal. The information of AC = BC was provided, and we knew the
information of 125°, so 180° – 125° = 55° (That means both Angles BAC
and ABC = 55°.) Thus, X = 180 – 55 – 55 = 70;
Y = 180 – 55 = 125.
Please contact me at chaosimo@msu.edu if you need help.
The figure below shows two concentric circles each with center O.
If the larger circle has radius 12 and the smaller circle has radius 8,
find the area of the shaded region.
From our Circles introduction chapter, we knew the area = radius² Л. Thus,
the area of the larger circle = 12² Л = 144 Л ; and the area of the smaller
circle = 8² Л = 64 Л; so the area of the shaded region should be:
144 Л - 64 Л = 80 Л.
Please contact me at chaosimo@msu.edu if you need help.
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