Lesson B

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Lesson B

• Review Angles,
• Triangles
• Polygons

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Angles
Straight angles Angles that measure 180º
180º
Right angles Angles measuring 90º
90º
Perpendicular lines lines that intersect at 90º
90º
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Acute angles angles measuring greater than zero
and less than 90º
Obtuse angles - angles measuring greater than 90º
and less than 180º
Adjacent angles angles that share a side
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Vertical angles angles that are across from
each other when two lines intersect
vertical angles are equal
Complementary angles two angles whose sum is
90º
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Supplementary angles - two angles whose sum is
180º
Practice
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Polygons
closed, two-dimensional geometric shapes whose
sides are line segments
Equiangular polygon polygon with all congruent
angles
Equilateral polygon polygon with all congruent
sides
Regular polygon - polygon with all congruent
angles and sides
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Triangles

• The sum of the angles in any triangle is 180º
• In any triangle, the angles opposite sides of
  equal lengths have equal measures - vise-versa
• Right triangle
• - triangle with one right angle.
• Acute triangle
• triangle with all acute angles

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More triangles
Obtuse triangle triangle with one obtuse angle
Isosceles triangle triangle that has at least
two sides of equal length and the angles opposite
are also equal.
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And more triangles
Equilateral triangle triangle in which the
lengths of all sides are equal.
Scalene triangle triangle in which all sides
have different length
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Practice
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Problem Set B Worksheet