Coordinate Geometry
Proving Parallelograms
Family Tree
Diagonals
Properties
100

If two segments have equal slopes, what does that prove?

They are parallel.

100

A quadrilateral has one pair of opposite sides that are both parallel and congruent.
Is it a parallelogram?

Yes.

100

Which shape is always both a rectangle and a rhombus?

Square

100

What do the diagonals of every parallelogram do?

They bisect each other.

100

What must be true about the opposite sides of every Parallelogram?

They are parallel and congruent.

200

f two segments have slopes that are negative reciprocals, what does that prove?

They are perpendicular.

200

A quadrilateral has diagonals that intersect at their midpoints.

Is it a parallelogram?

Yes. If the diagonals bisect each other, the quadrilateral must be a parallelogram.

200

Is every rhombus a parallelogram?

Yes

200

In a rectangle, what is always true about the diagonals?

They are congruent.

200

If one angle of a parallelogram is 90°, what type of quadrilateral is it?

Rectangle

300

Points: A(1,2), B(5,2), C(7,6), D(3,6)
What type of quadrilateral is ABCD?

Parallelogram

300

A quadrilateral has one pair of opposite sides parallel. Is it a parallelogram?

Unknown.

300

Is every rectangle a rhombus?

No

300

In a rhombus, what is always true about the diagonals?

They are perpendicular.

300

A quadrilateral has four congruent sides and opposite angles congruent. What is it?

Rhombus

400

A quadrilateral has diagonals with the same midpoint. What can you conclude?

It is a parallelogram.

400

A student says:
“The diagonals are congruent, so the quadrilateral is a parallelogram.”
Is the student correct? If not, what additional information is needed?

No. Congruent diagonals alone do not prove a parallelogram.

400

Name all 3 quadrilaterals that are always parallelograms.

Rectangle, rhombus, square

400

Which quadrilateral has diagonals that are both perpendicular and congruent?

Square

400

A quadrilateral has exactly one pair of parallel sides. What is it?

Trapezoid

500

Three vertices are A(0,0), B(4,0), C(6,3).
Find the fourth vertex to make a parallelogram.

(2,3)

500

A quadrilateral has:

  • Both pairs of opposite sides congruent

  • All angles are right angles

What is the most specific classification possible?

Rectangle

500

Which of these is NOT part of the parallelogram family: square, rhombus, kite, rectangle?

Kite

500

A quadrilateral has perpendicular diagonals, but they do NOT bisect each other. What is the most likely classification?

Kite.

500

Consecutive angles in a parallelogram always have what relationship?

They are supplementary.