Geometry Unit 7 Test Review

Diagonal

A diagonal that joins 2 non-consecutive vertices of a polygon

Convex

A polygon whose diagonals all lie inside the figure

Concave

A polygon where one or more diagonals lie outside the figure

Regular Polygon

A regular polygon that is both equilateral and equal angular

Heptagon

7-sided polygon

Nonagon

9-sided polygon

Decagon

10-sided polygon

Anything 11 sided and up…

n-gon

Interior angle

180 (n-2)

Exterior Angle

360 degrees

Parallelogram Opposite Sides Theorem

If a quadrilateral is a parallelogram, then its opposite sides are congruent

Parallelogram Opposite Angles Theorem

If a quadrilateral is a parallelogram, then its opposite angles are congruent

Parallelogram Diagonals Theorem

If a quadrilateral is a parallelogram, then its diagonals bisect each other

Parallelogram Consecutive Angles Theorem

If a quadrilateral is a parallelogram, then its consecutive angles are supplementary (THIS THEOREM CANNOT PROVE THAT A QUADRILATERAL IS A PARALLELOGRAM)

Rhombus

A parallelogram with 4 congruent sides

Rhombus Diagonals Theorem

A parallelogram is a rhombus if and both if its diagonals are perpendicular

Rhombus Opposite Angles Theorem

A parallelogram is a rhombus if and only if each diagonal bisects a pair of opposite angles

Rectangle Diagonals Theorem

A parallelogram is a rectangle if and only if its diagonals are congruent

Trapezoid

A quadrilateral with one pair of parallel sides

Isosceles Trapezoid Base Angles Theorem

If a trapezoid is isosceles, then each pair of base angles is congruent

Isosceles Trapezoid Diagonals Theorem

A trapezoid is isosceles if and only if its diagonals are congruent

Trapezoid Mid segment Theorem

Formula = ½ (AB + CB)

Kite Diagonals Theorem

If a quadrilateral is a kite then its diagonals are perpendicular

Kite Opposite Angles Theorem

If a quadrilateral is a kite, then exactly one pair of opposite angles are congruent