Transformations
Triangle Congruence
Relationships in Triangles
Vocabulary
Parallel and Perpendicular Lines
100

What type of transformation slides a figure without rotating or flipping it?

Translation

100

What does SSS stand for in triangle congruence?

Side-Side-Side

100

What is the name of a line segment that connects a vertex to the midpoint of the opposite side?

Median

100

What is the name of the point where the medians of a triangle intersect?

Centroid

100

What kind of angles are formed when a transversal crosses parallel lines?

Corresponding, alternate interior, alternate exterior, and same-side interior angles

200

What type of transformation flips a figue over a line?

Reflection

200

What triangle congruence theorem requires two angles and the included side?

ASA

200

In a triangle, the largest angle is always opposite the ________.

Longest side

200

What is the name of the point that is equidistant from all sides of a triangle?

Incenter

200

True or False: If two lines have the same slope, they are parallel.

True

300

A rotation of 90° clockwise around the origin maps (3, 4) to what point?

(4,-3)

300

Why is SSA not a valid triangle congruence theorem in most cases?

It doesn't guarantee congruence (ambiguous case)

300

The centroid of a triangle divides each median in what ratio?

2:1

300

What do you call a segment from a vertex perpendicular to the opposite side (or its extension)?

Altitude

300

What is the slope of a line perpendicular to a line with slope 2?

-1/2

400

What sequence of transformations maps a figure onto its mirror image across the y-axis and then moves it up 3 units?

Reflection over y-axis, then translation up 3 units

400

Name all the valid triangle congruence theorems.

SSS, SAS, ASA, AAS, and HL (for right triangles)

400

A triangle has two sides of lengths 7 and 10. What is the possible range for the third side?

Between 3 and 17 (not inclusive)

400

What is the name of the point where the perpendicular bisectors of a triangle intersect?

Circumcenter

400

If two parallel lines are cut by a transversal and one angle is 70°, what is the measure of the alternate interior angle?

70°

500

A triangle is reflected over the x-axis, then rotated 180° around the origin. Describe the single transformation that is equivalent.

Reflection over the line y = -x

500

Given △ABC ≅ △DEF, if AB = 5 cm and ∠C = 40°, what are the corresponding parts in △DEF?

DE = 5 cm, ∠F = 40°

500

Name all four special segments in a triangle and their points of concurrency.

Median – centroid, altitude – orthocenter, angle bisector – incenter, perpendicular bisector – circumcenter

500

What is the point of concurrency where the altitudes of a triangle intersect?

Orthocenter

500

Find the equation of a line perpendicular to y = 3x + 1 that passes through the point (2, 5).

y = -1/3x + 19/3 or y - 5 = -1/3(x - 2)