Download Year 9 Sheet 27

Year 9 - Worksheet 27
1.
Sketch the result if the two
solids are fitted with the
shaded faces together.
2.
How many blocks are needed to build the model on the right?
3.
if
1
1
2
represents
1
then draw:
ISBN: 9781877489143
1
3
2
1
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INTERIOR ANGLES OF POLYGONS
Below are two flow charts to find the interior angles of a regular polygon.
1.
Use each flow chart to calculate the size of the interior angle of two regular
polygons, one with 12 sides and one with 20 sides.
Let n = the number of sides in the polygon
Calculate n - 2
Divide 360 by n
Multiply by 180
Subtract from 180
Divide by n
The result is the size of the angle in degrees
Method 1
Method 2
Interior angle size of a 12 sided polygon:
Interior angle size of a 20 sided polygon:
In the diagram, three regular polygons fit together exactly at point P.
One possible situation is that the polygons could be three regular
hexagons. Give another possible combination of polygons that could fit
together way (it could be more than 3 polygons).
Polygon 3
Polygon 1
Polygon 2
Year 9, Worksheet 27, Page 2 - www.mathscentre.co.nz
ISBN: 9781877489143
2.
COORDINATES
1.
On the grid below, plot and join each of these co-ordinates.
A(-4, 4), B(-3, -3), C(2, -3), D(3, 4), A(-4, 4).
2.
Write the name of the shape that was formed.
3.
If each of the co-ordinates were placed at 1 cm intervals, what would the
area of the shape be?
y
5
4
3
2
1
-5 -4 -3 -2 -1
-1
0
1
2
3
4
5
x
-2
-3
Area =
cm
-4
2
-5
4.
On the axes below draw the following six triangles.
i.
(-5, 3), (-5, 5), (-2, 4) (-5, 3)
ii.
(-4, 1), (-1, 1), (-1, 5), (-4, 1)
y
iii.
(4, 5), (5, 2), (6, 5), (4, 5)
5
ISBN: 9781877489143
5.
iv.
(4, 1), (2, -1), (6, -3), (4, 1)
v.
(2, -2), (3, -5), (1, -5), (2, -2)
vi.
(-1, -5), (-5, -3), (-4, -1), (-1, -5)
Name the groups of triangles
that are congruent.
4
3
2
1
-5 -4 -3 -2 -1-1
-2
-3
-4
-5
0
1 2 3 4 5 6 x
Year 9, Homework Sheet 27, Page 3 - www.mathscentre.co.nz
CONSTRUCTIONS
1.
Using the point and the line given, construct the following triangle.
P
O
7 cm
M
10 cm
N
2.
On your diagram, measure the angle OMN.
=
°
3.
On your diagram measure the length of side MO.
=
cm
Year 9, Worksheet 27, Page 4 - www.mathscentre.co.nz
ISBN: 9781877489143
P