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Angles .
Angles are all around us.
Angles are formed when two lines meet .
If there are two straight
lines such that they have a common endpoint.
Then the amount of turn (curl) between these two lines is known as angle between those lines.
There are angles in most shapes and in many of the objects you
see and use on a daily basis .
Angles are measured in
degrees.
There are four types of
angles: acute angle, obtuse angle ,right angle, straight angle .
Let's find out more about these different types of angles.
Acute angle
When two straight lines
make an angle with each other such that it is greater than zero degrees and
less than 90 degrees.
Then these lines are said
to be making an acute angle with each other.
Some triangles have acute
angles.
Here are a few examples
the slice of pizza that you eat for lunch is an acute angle.
You get a new box of
pencils to take to school after you sharpen all of the pencils you notice that
the tips are acute angles.
Obtuse angle.
When two straight lines
make an angle with each other such that it is greater than 90 degrees and less
than 180 degrees.
Then these lines are said
to be making an obtuse angle with each other.
Many shapes such as pentagons, octagons and triangles have obtuse angles.
Let 's see what makes an obtuse angle .
You are walking by the water and you see a beautiful sailboat.
You notice that the sails have obtuse angles.
You notice that the sails have obtuse angles.
You are playing outside
with friends when you look up and notice that the top of your house is an
obtuse angle.
Right angle.
When two straight lines
are perpendicular to each other or make 90 degrees with each other. then they
are said to be at right angles.
Right angles are often shown with a box in the
corner that let you know that it is
exactly 90 degrees.
Squares and rectangles
are formed using right angles.
Let 's look at a few examples.
You are looking out the
window of your house .
You notice that the window panes are formed by right angles.
You are exploring a new
city with your family .
You notice that many of
the buildings are built out of brick.
The bricks all form right angles.
Straight angle .
When two line segments
point exactly in the opposite direction and form a single straight line ,then
the angle they form is a hundred and eighty degrees or straight angle.
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