Lesson 1 12 Angles Triangles and Quadrilaterals Vocabulary

Lesson 1 -12 Angles, Triangles, and Quadrilaterals Vocabulary: angle, vertex, right angle, perpendicular, obtuse angle, acute angle, right triangle, trapezoid kite, and polygon

right angle acute angles right triangle vertex Perpendicular angles

kite A trapezoid is a 4 sided flat shape with straight sides that has a pair of opposite sides parallel

Polygons are 2 -dimensional shapes (having or appearing to have length and breadth but no depth). They are made of straight lines, and the shape is "closed"

Math Message Make geometric shapes. Try different shapes.

In this lesson you will construct 2 dimensional shapes. 1. Angles meet at points called the vertex. 2. A right angle is an angle whose sides form a square corner, similar to an L. 3. Lines or line segments that intersect and form right angles are called perpendicular lines or line segments. 4. Draw right angle HRM. Line segment RH is perpendicular to line segment RM. 5. An obtuse angle is an angle larger than a right angle. Show me an obtuse angle. 6. An acute angle is an angle smaller than a right angle.

An angle is made up of two (2) rays that have the same endpoint – the vertex of the angle. An angle can also be made of two line segments that share the same endpoint. What is another name for angle ABC? Fyi – the middle letter in the name of an angle always names the vertex.

1. 2. 3. 4. 5. 6. Join three (3) different lengths together. What is the shape? How many “right” angles are in a triangle? Sides that form a right triangle are “perpendicular” to each other. Draw a right triangle and label the vertices X, Y, and Z. Line segment XY is perpendicular to line segment YZ. Can you identify perpendicular line segments in the classroom?

Make four (4) sided shapes. (1) What is a four sided shape called? Create a four sided shape in which all sides are the same size and all angles are right angles. What is the shape called? square quadrilaterals

Make four (4) sided shapes. (2) Pull two opposite corners of the square outward. Are the angles still right angles? Are all sides still the same length? What is the new shape called? rhombus quadrilaterals

Make four (4) sided shapes. (3) Make a shape that has two sides of one length and two sides of a different length with four (4) right angles. What is this shape called? rectangle quadrilaterals

Make four (4) sided shapes. (4) Pull two opposite corners of the rectangle in opposite directions. Are the angles still right angles? Are the pairs of opposite sides still the same length? What is this shape called? parallelogram quadrilaterals

Triangles and quadrilaterals are all examples of polygons.

Practice Time Work on page 29 and 30 in your math journal.

Exit Ticket Draw a acute angle, right angle, and an obtuse angle.