geometry terms

Cosine

in a right triangle, the ratio of the length of the leg adjacent to the angle and it's hypotenuse.

angle of elevation

the angle formed by a horizontal line and a line of sight a point above.

geometric mean

for positive numbers a and b the positibe number x such as a/x= x/b.

angle of depression

the angle formed by a horizontal line and a line of sight to a point below.

sine

in a right triangle, the ratio of the length of the leg opposite the angle to the length of the hypotenuse.

tangent

in a right triangle, the ratio of the length of the leg opposite the angle to the length of the leg adjacent to the angle.

trigonometric ratio

a ratio of two sides of a right triangle

similarity ratio

the ratio of two corresponding linear measurements in a pair of similar figures.

indirect measurement.

a method of measuring an object by using formulas, similar figures and or proportions.

dilation.

a drawing that uses a scale to represent an object smaller or larger than the original object.

scale

the ratio of any length in a drawing to the corresponding actual length.

scale drawing

a transformation in which the lines connecting every point P with its pre image P' all intersect at point C, and CP'/CP is the same for every point P or a transformation that changes the size of its figure but not its shape.

scale factor

in a dilation, the ratio of a linear measurement of the image to the corresponding measurement of the pre image.

similar

two figures that have the same shape but not necessarily the same size.

similar polygons

two polygons whose corresponding angles are congruent and whose corresponding sides are proportional.

cross products

in the statement a/b=c/d, the product of the means bc and the product of the extremes ad

ratio

a comparison of two numbers by division

means

b and c in the proportion a/b=b/d

extremes

a and d in the proportion a/b=c/d

proportion

an equation that states that two ratios are equal.