Geometry Ch 10 - Area Flashcards
Area of Rectangle
A = bh
Area of Parallelogram
A = bh where h is the corresponding height.

Base of a Parallelogram is…
… any of its sides. the corresponding altitude is a segment perpendicular to the line containing that base, drawn from the side opposite the base. The height is the length of an altitude.

Area of a Triangle
A = 1/2(bh)

Base of a Triangle
Any of it’s sides.
Corresponding Height of Triangle
The length of the altitude to the line containing the base of a triangle.
Height of a Trapezoid
The perpendicular distance h between the bases.

Area of a Trapezoid
A = 1/2[h (b1 + b2)]

Area of a Rhombus or a Kite
A = 1/2(d1d2)

Radius of a Regular Polygon
The distance from the center to a vertex.

Apothem of a Regular Polygon
The perpendicular distance from the center to a side.

Area of a Regular Polygon
A = 1/2(ap) where a = the apothem and p = the perimeter.

Perimeters and Areas of Similar Figures
If the similarity ratio of two similar figures is a/b, then
(1) the ratio of their perimeters is a/b and
(2) the ratio of thier areas is a2/b2
Area of a Triangle given SAS
The area of a triangle is one half the product of the lengths of two sides and the sine of the included angle.
Area = 1/2[bc(sin A)

Law of Sines and Cosines

Circle
In a plane, it’s the set of all points equidistant from a given point called the center. You name it by it’s center.

Radius
A segment that has one endpoint at the center and the endpoint on the circle.
Congruent Circles
Have congruent radii.
Diameter
A segment that contains the center of a circle and has both endpoints on the circle.
Central Angle of a Circle
An angle whose vertex is the center of the circle.
Arc
A part of the circumference of a circle or other curve.
Semicircle
One type of an arc that contains half a circle.
Minor Arc
Is smaller than a semicircle.
Major Arc
An arc that is geater than a semicircle.






