unit 5 stuff idk man Flashcards
Parallelogram
A quadrilateral w/ both pairs of opp. sides parallel
If a quadrilateral is a parallelogram (1)
Then the opp. sides are congruent
If a quadrilateral is a parallelogram (2)
Then opp. angles are congruent
If a quadrilateral is a parallelogram (3)
Then its diagonals bisect each other
If both pairs of opp. sides of a quad. are congruent,
Then the quad. is a parallelogram
If both pairs of opp. angles of a quad. are congruent
Then the quad. is a parallelogram
If the diagonals of a quad. bisect each other,
Then the quad. is a parallelogram
If one pair of opp. sides of a quad are both congruent and parallel,
Then the quad. is a parallelogram
If two lines are parallel
Then all points on one line are equidistant from the other line
If 3 parallel lines cut off congruent segments on one transversal,
Then they cut off congruent segments on every transversal
A line that contains the midpoint of one side of a triangle and is parallel to another side,
passes through the midpoint of the third side
The segment that joins the midpoints of two sides of a triangle is (2 THINGS)
- Parallel to the third side
- Is half as long as the third side
Rectangle (DEF)
A quad. with 4 right angles
Rhombus (DEF)
A quad. with 4 congruent sides
Square (DEF)
A quad. with 4 right angles and 4 congruent sides
The diagonals of a rectangle-
-are congruent
The diagonals of a rhombus-
-are perpendicular
Each diagonal of a rhombus bisects-
-two angles of the rhombus
The diagonals of a parallelogram-
-bisect each other
The midpoint of the hypotenuse of a right triangle is-
-equidistant from the 3 vertices
If an angle of a parallelogram is a right angle,
Then the parallelogram is a rectangle (HAS to be a parallelogram)
If 2 consecutive sides of a parallelogram are congruent,
Then the parallelogram is a rhombus
EX: In parallelogram ABCD, the diagonals meet at point E and AE=6, and BE+6. IS ABCD a rectangle?
Yes, because a parallelogram w/ congruent diagonals mean its a rectangle
ES: You cut a parallelogram shaped quilt piece and measure the diagonals to be congruent. What is the shape?
Rectangle because the diagonals of the parallelogram are congruent
An angle formed by the diagonals of the quilt piece measures 90 degrees. Is the shape a square?
Yes, cuz its a rectangle and a rhombus at the same time
Trapezoid (DEF)
quad. with exactly one pair of parallel sides
Base (TRAPEZOID DEF)
Parallel sides
Leg (TRAPEZOID DEF)
Non-parallel sides
Isosceles Trapezoid
A trapezoid with congruent legs
Base angles of an isosceles trapezoid are-
-congruent
Median of a trapezoid
The segment that joins the midpoints of the legs
The median of a trapezoid- (2 THINGS)
- Is parallel to the bases
- Has a length equal to the average of the base lengths
FAMILY TREE!!!
Polygons
↓
Quadrilaterals
↙ ↘
Parallelograms Trapezoids
↙ ↘ ↓
Rectangles Rhombus Isosceles Trapezoids
↘ ↙
Square