Answer:
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<u>Skills needed: Angle Geometry</u>
Step-by-step explanation:
1) First, let's see what we should know prior to solving.
---> We have to find the value of
, and looking at that diagram, we have to create an equation.
---> The angle measure of a straight line is 180 degrees, otherwise known as a straight angle (a straight angle is 180 degrees).
---> When you add
, you can set that sum equal to 180. This is because the two angles marked
added together make a straight line, which is a straight angle.
(Note: In geometry, ONE OF THE THINGS WE CAN ASSUME is that there is a straight line there.)
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2) Now, the equation would be:

--> Combining
and
(3+3 = 6)
--> Dividing by 6 on both sides, to get
by itself.
--->
is 30, so
is equal to 30.
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