5/10/17 Week 6 Wednesday daily sheet:
2-D shapes/ Perimeter
Daily aims:
 1. I can recognize 2-D shapes, such as squares, rectangles, triangles, circles, parallelograms, trapezoids,
and various common polygons (pentagon, hexagon, octagon).
 2. I can calculate the perimeter of 2-D shapes.
 3. I can figure out the perimeter of complex shapes with a side length missing.
 4. I can work “backwards” from the perimeter of a 2-D shape to a missing side length.
 5. I can calculate the perimeter of shapes with side lengths that are algebraic expressions.
Before lesson
1) Label all the 2-D shapes on the Labeling 2-D shapes
handout.
During lesson
1) Draw & label any 2-D shape you didn’t recognize.
2) What’s the difference between perimeter and area?
3) What’s the perimeter
of this triangle?
4) A regular hexagon has a side length of 2.3 m.
What’s its perimeter?
D. Stark 5/10/2017
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7 ft.
12 ft.
5) Calculate the perimeter of the room.
10 ft.
18 ft.
6) The perimeter of a rectangle is 16 in, and its length is
6 in. What’s the width? (HINT: Draw a diagram.)
7) If the perimeter of the quadrilateral PQRS is 18 in,
what’s the value of x?
http://www.mathworksheets4kids.com/quadrilateral/unknown-sides1.pdf
D. Stark 5/10/2017
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5/10/17 Week 6 Wednesday daily sheet:
2-D shapes/ Perimeter
Before lesson
1) Label all the 2-D shapes on the Labeling 2-D shapes
handout.
KEY
During lesson
1) Draw & label any 2-D shape you didn’t recognize.
See answer key for handout.
2) What’s the difference between perimeter and area?
Perimeter is the distance around a shape.
(Think of using your pedometer to count steps.)
Area is the space inside a 2-D shape.
3) What’s the perimeter
of this triangle?
P = 1 ¼ + ¾ + ½ = 2 ½ in.
Notice that you can add in any order. You can do
so here so the quarters total up neatly without
having to deal with common denominators.
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4) A regular hexagon has a side length of 2.3 m.
What’s its perimeter?
P = 6(2.3) = 13.8 m
2.3 m
A regular polygon has congruent sides (sides with
the same length). The hash marks here indicate
congruence.
7 ft.
12 ft.
5) Calculate the perimeter of the room.
10 ft.
18 ft.
P = 18 + 12 + 8 + 7 + 10 + 5 =
60 ft
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6) The perimeter of a rectangle is 16 in, and its length is
6 in. What’s the width? (HINT: Draw a diagram.)
6 in.
?
P = 16
?
6 in.
Without algebra:
6 + 6 = 12 Since P = 16, there’s 16 – 12 = 4
left to be divided between each side.
The width is 2 in.
With algebra:
P = 2L + 2w
16 = 2(6) + 2w
16 = 12 + 2w
[from formula sheet]
4 = 2w
w = 2 in.
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7) If the perimeter of the quadrilateral PQRS is 18 in,
what’s the value of x?
3x + 1 + 3 + 6 + x = 18
3x + 1 + 3 + 6 + x = 18
4x + 10 = 18
4x + 10 = 18
4x = 8
4x = 8
x=2
http://www.mathworksheets4kids.com/quadrilateral/unknown-sides1.pdf
D. Stark 5/10/2017
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