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Angles
Common Core Standard: Use facts about supplementary, complementary, vertical, and adjacent angles in a multi-step
problem to write and solve simple equations for an unknown angle in a figure.
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Supplementary angles- are angles that have a sum of 180o
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Complementary angles- are angles that have a sum of 90o
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Congruent – means that two figures have the same measure; the symbol for congruency is 
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Vertical angles – are two angles that are across from each other that are congruent
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Adjacent angles – are two or more angles that are next to each other that form a straight line, which means that
the angles are supplementary
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Example: Determine the value of the missing angles below
o
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These angles are adjacent, which means that the angle are supplementary
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Supplementary angles measure 180o
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So, 180o – 44o = 136o
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x = 136o
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These are vertical angles
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This means that the angles are congruent or equal
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11y – 36 = 63
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Combine like terms 36 and 63
o
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11y – 36 + 36 = 63 + 36
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11y= 99
Divide both sides by 11
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y=9
o
Two angles are complementary. One angle measures 44.5o. What does the other angle measure?
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Complementary angles have a sum of 90o
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44.5o + z = 90o, z= missing angle
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44.5o – 44.5o + z = 90o - 44.5o
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z = 45.5o
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Transversal Example:
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Transversal – is a segment that intersects two parallel lines
o
Looking at this picture, we can identify different types of angles
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<2  <4, because they are vertical angles
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<1  <3, because they are vertical angles
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<5  <7, because they are vertical angles
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<6  <8, because they are vertical angles
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<1 is supplementary to <2, because they are adjacent angles
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<1 is supplementary to <4, because they are adjacent angles
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<2 is supplementary to <3, because they are adjacent angles
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<5 is supplementary to <6, because they are adjacent angles
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<5 is supplementary to <8, because they are adjacent angles
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<6 is supplementary to <7, because they are adjacent angles
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<7 is supplementary to <8, because they are adjacent angles