Points of Concurrency

Altitude

Is a median, altitude, angle bisector, or perpendicular bisector shown?

Median

Is a median, altitude, angle bisector, or perpendicular bisector shown?

Perpendicular Bisector

Is a median, altitude, angle bisector, or perpendicular bisector shown?

Angle Bisector

Is a median, altitude, angle bisector, or perpendicular bisector shown?

Orthocenter

The three altitudes of a triangle intersect at the
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Centroid

The three medians of a triangle intersect at the
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Circumcenter

The three perpendicular bisectors of a triangle intersect at the
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Incenter

The three angle bisectors of a triangle intersect at the
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Circumcenter

It is equidistant from the three vertices of a triangle.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Incenter

It is equidistant from the three sides of a triangle.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Centroid

It divides each median into two sections at a 2:1 ratio.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Centroid

The ___ is the center of gravity or balancing point of a triangle.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Euler

The centroid, circumcenter, and orthocenter are collinear. They all lie on a straight line called the ___ line.

Midsegment

Segment DE is called a ____.

8

If DE = 4, then AB = ?.

6

If AB = 12, then DE = ?.

True

T or F. Segment AB is parallel to segment DE.

Centroid

The triangle center shown is the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Circumcenter

The triangle center shown is the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Incenter

The triangle center shown is the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Circumcenter

The triangle center shown is the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Orthocenter

The triangle center shown is the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Incenter

The triangle center shown is the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Incenter

The triangle center shown is the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Circumcenter

The triangle center shown is the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Orthocenter

The triangle center shown is the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Circumcenter

The triangle center shown is the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Incenter

The triangle center shown is the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Circumcenter

The triangle center shown is the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Circumcircle

Is the circle an incircle or a circumcircle?

Incircle

Is the circle an incircle or a circumcircle?

Circumenter

The ___ of a right triangle is located on the midpoint of its hypotenuse.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Orthocenter

The ___ of a right triangle is located on a vertex.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

True

True or False. The triangle centers are located inside an acute triangle.

16

If SV = 8, then VR = ?

11

If VP = 22, then VT = ?

9

If UV = 3, then QU = ?.

27

If VR = 18, then SR = ?

10

If SR = 30, then VS = ?

16

If PT = 24, then PV = ?

Isosceles

In a(n) ___ triangle, the points of concurrency are collinear and do not coincide.
a. scalene
b. isosceles
c. equilateral
d. obtuse

Equilateral

In a(n) ___ triangle, the points of concurrency coincide
a. scalene
b. isosceles
c. equilateral
d. obtuse

Orthocenter and Circumcenter

Which two points of concurrency are always located outside of an obtuse triangle?
a. incenter
b. circumcenter
c. centroid
d. orthocenter

Median

The line segment joining a vertex to the midpoint of the opposing side is the ___.
a. median
b. altitude
c. angle bisector
d. perpendicular bisector

Angle Bisector

The segment drawn from a vertex that bisects that vertex angle is the ___.
a. median
b. altitude
c. angle bisector
d. perpendicular bisector

Altitude

The perpendicular segment from a vertex to its opposite side is the ___.
a. median
b. altitude
c. angle bisector
d. perpendicular bisector

...

The line segment that is both perpendicular to a side of a triangle and passes through its midpoint is the ___.
a. median
b. altitude
c. angle bisector
d. perpendicular bisector

7

G is the incenter. If FG = 7, then GD = ?

2

G is the incenter. If FG = 7 and EG = 3x + 1, then x = ?

30

G is the incenter. If the measure of angle GAD = 30�, then the measure of angle GAE = __________�.

60

G is the incenter. If the measure of angle GAD = 30�, then the measure of angle DAE = __________�.

13

C is the circumcenter. If DF = 13, then BF = ?

10

C is the circumcenter. If CD = 10, then CB = ?

2

C is the circumcenter. If CD = 10 and CA = 4x + 2, then x = ?

90

C is the circumcenter. The measure of angle CGB is ___�.

Circumcenter

The distance from the centroid to the orthocenter is twice the distance from the centroid to the ___.
a. incenter
b. circumcenter
c. centroid
d. orthocenter

16

BC = ?

5.5

PR = ?

9.5

ML = ?

34�

Find the measure of angle DBC if the measure of angle ABD = 68�.

64�

Find the measure of angle TSU.

Possible Answer: y - 5 = -2(x - 1)

Write an equation in point-slope form for the perpendicular bisector of the segment with endpoints S(-1, 4) and B(3, 6).

20.9

Find JZ.

(4, 3)

Find the circumcenter of a triangle with vertices at (0, 0), (8, 0) and (0, 6).

17�

V is the incenter. Find the measure of angle VKL.

Circumcenter

The building contractor for a city wants to build a public restroom in a park equidistant from the three recreation areas. Where should the restroom be located?
a. At the centroid
b. At the orthocenter
c. At the incenter
d. At the circumcenter

47�

What is the measure of angle SVU?

always

A triangle (always, sometimes, never) has 3 medians.

sometimes

An altitude is (always, sometimes, never) a median.

True

True or False. Each leg of a right triangle ABC is an altitude of ABC.

False

True or False. The three angle bisectors of a triangle intersect at a point outside the triangle.

False (5 + 7 is not > 12)

True or False. The measures 5, 7, and 12 can be the side lengths of a triangle.

True (6 + 7 > 12)

True or False. The measures 6, 7, and 12 can be the side lengths of a triangle.

False (5 + 7 is not > 14)

True or False. The measures 5, 7, and 14 can be the side lengths of a triangle.

True

True of False. The sum of the lengths of any two sides of a triangle is greater than the length of the third side.

right

A triangle has side lengths a, b, and c. The longest side length is c. If a� + b� = c�, the the triangle is a(n) _____ triangle.

obtuse

A triangle has side lengths a, b, and c. The longest side length is c. If a� + b� < c�, the the triangle is a(n) _____ triangle.

acute

A triangle has side lengths a, b, and c. The longest side length is c. If a� + b� > c�, the the triangle is a(n) _____ triangle.

hinge theorem

If QR > UV, then angle T ___ angle S.

False (must be right triangle)

True or False. If a triangle has side lengths that measure 5, 5, and 5 then the side lengths form a Pythagorean Triple.

Pythagorean Triple

Any three natural numbers (1, 2, 3, ...) that satisfy the Pythagorean Theorem.

1 : 1 : ?2

45-45-90 triangle ratio?

1 : ?3 : 2

30-60-90 triangle ratio?

?2

Given a 45-45-90 triangle, you can find the length of a leg by dividing the hypotenuse by ___.

?2

Given a 45-45-90 triangle, you can find the length of the hypotenuse by multiplying either leg by ___.

2

Given a 30-60-90 triangle, you can find the length of the hypotenuse by multiplying the short leg by ___.

?3

Given a 30-60-90 triangle, you can find the length of the longer leg by multiplying the short leg by ___.