Download Diapositiva 1

____(0-10 pts) Describe a ratio. Describe a proportion. How are they related?
Describe how to solve a proportion. Describe how to check if a proportion is
equal. Give 3 examples of each.
Ratios: they compare two numbers by division.
Proportions: is an equation stating that two ratios are equal.
Relationship: ratios relates two quantities together using a fractions
a proportion has a relationship between two quantities the equivalence of two ratios.
Checking: to check if a proportions are equal you have to cross multiply and obtain
The same result.
Ex:
x/2 = 40/16 x = 5 the proportion is equal.
x/5 = 10/6 x = 3 the proportion in not equal.
7/y = 21/27 y = 9 the proportion is equal.
_____(0-10 pts) Describe what it means for two polygons to be similar. What is
a scale factor? Give at least 3 examples of each.
Two polygons to be similar: For two polygons to be similar they need to have
Corresponding angles are congruent and their corresponding side lenghts are
Proportional.
Scale factor: the scale factor describes how much the figure is enlarged or reduced.
Ex:
1: It is similar.
2: They are similar polygons
3: They are similar polygons.
____(0-10 pts) Describe how to find the scale factor for the perimeter and
areas of similar figures. Give at least 3 examples of each one.
Similarity ratio: AB/DE = AC/DF = BC/EF = ½
Perimeter ratio: perimeter /perimeter
Are ratio : area/ area = ½ *2
_____(0-10 pts) Describe how to use similar triangles to make an indirect
measurement. Give at least 3 examples.
An indirect measurment any method that uses formulas, similar figures,
And / or proportions to measure an object.
These is use because to use a triangle that you do know there measurments and that
With that you only need to know one measurment of the object you want to measure
becasue you can use cross multiply.
_(0-10 pts.) Describe the right triangle altitude proportionality theorem. Give at
least 3 examples. Explain how the proportions can be used to solve real life
problems.
The altitude to the hypotenuse of a right triangle forms two triangles that are
Similar to the original triangle.
The proportions can be used to to solve real life figures because if you are climing
A mountain and you have 20 ft of rope and you need to find out how tall the mountain is
You use similar figures to find it oput and see if you have enogh rope.
__(0-10 pts.) Describe the three trigonometric ratios. Explain how they can
be used to solve a right triangle. What does it mean to solve a triangle? Give
at least 3 examples of each. How are they used in real life?
The sin: the sin of an angle is the ratio of the lenght of the leg opposite
The angle to the lenght of the hypotenuse.
The cosine of an angle is the ratio of the lenght of the leg adjacent to the angle
To the lenght of the hypotenuse.
The tangent of an angle is the ratio of the lenght of the leg opposite the angle to the
Length of the leg adjacent to the angle.
Cos 60 = 0.99
Tan 30 =0.57
Sin 45 = 0.70
_____(0-10 pts.) Compare an angle of elevation with an angle of depression. How
are each used? Give at least 3 examples of each
An angle of elevation is the angle formed by a horizontal line and a line of sight
To a point above the line.
An angle of depresion is the angle formed by a horizontal line and a line of sight to a point
Below the line.