geometry

33 terms · here is just some basic geometry stuff to remember

parallelogram

diagonals bisect each other
opposite sides are parallel

rectangle

diagonals are congruent
diagonals bisect each other
all angles are right angles
opposite sides are parallel

rhombus

diagonals are perpindicular
diagonals bisect each other
diagonals bisect each angle
all sides are congruent
opposite sides are parallel

square

HAS EVERYTHING:
diagonals are perpindicular
diagonals are congruent
diagonals bisect each other
diagonals bisect each angle
all sides are congruent
opposite sides are parallel
all angles are right angles

rectangle

A square is also a _________ and a rhombus

might

A rhombus ____ be a square

equilateral

all sides and angles are congruent in the triangle

isoceles

two sides are congruent ; and this is an obtuse triangle

45 45 90

what type of special right triangle is when: two sides are congruent and the hypotnuse = a side * √2 ?

30 60 90

what type of special right triangle do you :
to find shortleg: /2 or /√3
to find longleg: find short leg then *√3
to find hypotnuse: find short leg then *2

triples

(these are on pg 295 in txtbook)
here are the most common ones:
3,4,5
5,12,13
8,15,17
6,8,10
9,12,15
15,20,25

a²+b²=c²

sine

soh : opposite / hypotnuse

hypotnuse

longest side opposite the right angle

congruent

chords equally distant from the center are ______.
(Thm 9-6)

minor arc

this arc is less than half the circle

major arc

this arc is more than half the circle

semicircle

this arc is one half the circle

central angle

angle with the vertex at the center, this angle equals the length of the arc

true

all radii are congruent in a circle

half

The measure of an inscribed angle is _____ the measure of the intercepted arc.

right angle

An angle inscribed in a semicircle is a ______________. (It equals 90 degrees)

If a ___________ is inscribed in a circle, the opposite angles are supplementary (equal to 180°)

obtuse

c² ≥ a² + b² .......this formula equals what type of triangle (angle wise)

acute

c² ≤ a² + b² .......this formula equals what type of triangle (angle wise)

right

c² = a² + b² .......this formula equals what type of triangle (angle wise)

8/100

To find the grade of a road of 8% what fraction would you set up?

bottom

When equation refer to a "shadow" where do you draw that? On the ______ of the triangle.

congruent

tangents to a circle from a point are __________.

chord

segment whose endpoints are on the circle (notation is two capital letters with a line segment on top)

secant

a line that runs throught the circle (for notation make sure it has arrows on the line)