Download Visual Glossary - The Krusty KRABs

Visual Glossary
By: Anya Khosla
Unit 6
Introduction
Most people in this world know how to read. Everywhere you go, people are always reading. From
emails on their smartphones to books, people are reading. But what is reading without knowing
what the words mean?! If you don’t know what anything means, you won’t be able to understand
anything. To look up words, people use dictionaries.
This power point is like a dictionary, but on math concepts. These terms which you are about to see
are important terms which will help you understand unit 6 (unit 6 being the “book”).
I chose these terms because work in unit 6 will be easier if these terms are known. They are the
need-to-know terms so that you understand the unit. By knowing the definition of these terms,
solving problems in this unit will be easier. If word problems give you the values of one of these
terms (ex. Angle of elevation), you will know exactly where that value is located when drawing the
diagram. They can help create equations which are needed to solve the problem. 
LESSON 1
Dilation
• To enlarge or reduce a figure by a certain amount (scale factor)
When the original figure is dilated, the figure can either get bigger or smaller. In this example, it got
smaller. The side lengths have to be reduced (in this case) by the same amount to get the smaller
dilated figure. The original sides have to be dilated by a fraction to get a smaller dilated figure.
Scale Factor
• How much the figure is enlarged or reduced by
The scale factor is the number in which the sides
are enlarged or reduced by. As stated in the previous
slide, to get a reduced figure you have to have a scale
factor that is a fraction. To get an enlarged figure,
the scale factor is going to be a whole number
greater then 1.
LESSON 4
Geometric Mean
The geometric mean of two positive numbers is the positive square
root of the product of those two numbers.
The geometric mean is used to find ratios
between two sides in a right triangle
(trigonometric ratio). The ratios of the sides
are the geometric means of those two sides.
LESSON 5
Trigonometric Ratio
• The ratio of two sides of a right triangle
Three different types of trigonometric ratios are sine, cosine, and tangent of an angle. To find the
sine, cosine, or tangent of an angle, a ratio between two sides of the right triangle will always have
to be created. That ratio between the two sides is the trigonometric ratio.
Sine
• The sine of an angle is the ratio of the leg opposite the angle to the
length of the hypotenuse
To find the sine of an angle, you have to create a
Trigonometric ratio. You always have to make sure that
the mode on the calculator is in “degree mode” or else
you won’t get the sine of the angle. Since an angle is
measured in degrees, the Sine has to be in degrees also
because we are finding the Sine of the angle.
Cosine
The cosine of an angle is the ratio of the leg adjacent the angle to the
length of the hypotenuse
To find the cosine of an angle, you have to create a
Trigonometric ratio. You always have to make sure that
the mode on the calculator is in “degree mode” or else
you won’t get the cosine of the angle. Since an angle is
measured in degrees, the cosine has to be in degrees also
because we are finding the cosine of the angle.
Tangent
The tangent of an angle is the ratio of the leg opposite the angle to the
length of the leg adjacent to the angle.
To find the tangent of an angle, you have to create a
Trigonometric ratio. You always have to make sure that
the mode on the calculator is in “degree mode” or else
you won’t get the tangent of the angle. Since an angle is
measured in degrees, the tangent has to be in degrees also
because we are finding the tangent of the angle.
LESSON 6
Angle of elevation
The angle formed by a horizontal line and a line of sight above the line.
In the diagram on the right, the base angle next
to the 90 degree angle is the angle of elevation
because it’s the angle formed by a horizontal
line (the base) and the line of sight (the sun).
The angle is above the base line, making it an
elevation.
Angle of depression
The angle formed by a horizontal line and a line of sight to a point
below the line.
In the diagram on the right, the top angle is the
angle of depression. Imagine an imaginary
horizontal line, parallel to the base,
running from the sun. The angle is under the
Imaginary horizontal line, making it an angle of
Depression.