An isosceles triangle has a base of length 4 centimetres and a perimeter of 20 centimetres.
Find the length of the equal sides. (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
Aussie Maths & Science Teachers: Save your time with SmarterEd
An isosceles triangle has a base of length 4 centimetres and a perimeter of 20 centimetres.
Find the length of the equal sides. (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(8\ \text{cm}\)
\(\text{Let the length of the equal sides be}\ x\)
\(\text{Then,}\ \ 2\times x+4\) | \(=20\) |
\(2x\) | \(=20-4\) |
\(2x\) | \(=16\) |
\(x\) | \(=8\) |
\(\therefore\ \text{The equal sides are of length }8\ \text{cm}\)
--- 2 WORK AREA LINES (style=lined) ---
--- 2 WORK AREA LINES (style=lined) ---
--- 2 WORK AREA LINES (style=lined) ---
--- 2 WORK AREA LINES (style=lined) ---
a.
b. \(54\ \text{mm}\)
a.
b. \(\text{Perimeter}\)
\(=13+2\times 9+4+2\times 5+3+6\)
\(=54\ \text{mm}\)
--- 2 WORK AREA LINES (style=lined) ---
--- 4 WORK AREA LINES (style=lined) ---
a.
b. \(52\ \text{cm}\)
a.
b. \(\text{Perimeter}\)
\(=12+14+5+10+7+4\)
\(=52\ \text{cm}\)
A farmer uses the river bordering his property and fencing to create a large grazing paddock for his horses, as shown in the diagram below.
The fencing has 4-strand wiring which is also shown below.
Given that fencing is not required on the river boundary, how many kilometres of wire will be required to fence the rest of the paddock? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(5.6\ \text{km}\)
\(\text{Wire needed}\)
\(=4\times(700+200+300+1100+200+200+1200)\)
\(=4\times 3900\)
\(=15\ 600\ \text{m}=15.6\ \text{km}\)
Jill cut a piece of binding in half.
She then placed one half on top of the other half, as shown below.
What is the perimeter of the newly formed shape in millimetres? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(1600\ \text{mm}\)
\(\text{Calculating the perimeter clockwise from top right:}\)
\(\text{Perimeter}\)
\(=18+2\times 382 +18+2\times 400\)
\(=1600\ \text{mm}\)
Martha cut a piece of material in half as shown below.
She then placed the one half on top of the other half, as shown below.
What is the perimeter of the newly formed shape in millimetres? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(320\ \text{mm}\)
\(\text{Calculating the perimeter from the top down:}\)
\(\text{Perimeter}\)
\(=30+2\times 50+2\times 25+2\times 30+80\)
\(=320\ \text{mm}\)
A rectangle has a length of 12 cm and a width of 7 cm.
A square has the same perimeter as this rectangle.
What is the side length of this square in centimetres? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(9.5\ \text{cm}\)
\(\text{Perimeter of Rectangle}\)
\(=2\times 12 +2\times 7\)
\(=38\ \text{cm}\)
\(\text{Side length of square}\)
\(=\dfrac{38}{4}\)
\(=9.5\ \text{cm}\)
A hexagon with equal sides and an equilateral triangle are drawn below.
3 identical hexagons and 8 identical equilateral triangles are connected as shown in the diagram below.
What is the perimeter of the larger shape?
\(D\)
\(\text{Perimeter}\)
\(=\text{Number of sides}\times 8.5\)
\(=22\times 8.5\)
\(=187\ \text{mm}\)
\(\Rightarrow D\)
Joyce is walking her dog around a paddock in the shape of a parallelogram.
If she walks the dog around the paddock in the morning and the afternoon, how many kilometres do they walk each day? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(14.8\ \text{km}\)
\(\text{Perimeter of paddock}\)
\(=2\times 1.4+2\times 2.3\)
\(=7.4\ \text{km}\)
\(\text{Total distance walked each day}\)
\(=2\times 7.4\)
\(=14.8\ \text{km}\)
\(C\)
\(\text{Perimeter}=4\times d=4d\)
\(\text{Options A, B and D}=4d\)
\(\text{Option C}=d\times d=d^2\ne 4d\)
\(\Rightarrow C\)
Tatiana is cutting a piece of material in the shape of a parallelogram for a sewing project.
The longer sides are one and two-thirds times the length of the shorter sides.
What is the perimeter of the piece of material? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(96\ \text{cm}\)
\(\text{Longer side}\) | \(=\dfrac{5}{3}\times 18\) |
\(=30\ \text{cm}\) |
\(\therefore\ \text{Perimeter}\) | \(=2\times 18 +2\times 30\) |
\(=96\ \text{cm}\) |
Fumiko is laying pavers that are shaped like a parallelogram.
The longer sides are 3.5 times the length of the shorter sides.
What is the perimeter of one of the pavers? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(72\ \text{cm}\)
\(\text{Longer side}\) | \(=8\times 3.5\) |
\(=28\ \text{cm}\) |
\(\therefore\ \text{Perimeter}\) | \(=2\times 8 +2\times 28\) |
\(=72\ \text{cm}\) |
What is the perimeter of the shape below given each square has a side length of 2 cm? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(40\ \text{cm}\)
\(\text{Starting from bottom right moving clockwise.}\)
\(\text{Perimeter}\) | \(=12+2+2+2+2+2+6+4+2+6\) |
\(=40\ \text{cm}\) |
A rectangular parking lot has a perimeter of 80 metres.
Each short side has a length of 10 metres.
What is the length of the long side? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(30\ \text{m}\)
\(\text{Let}\ \ d=\text{long side of parking lot}\)
\(2\times d + (2\times 10)\) | \(=80\) |
\(2d\) | \(=80-20\) |
\(2d\) | \(=60\) |
\(\therefore\ d\) | \(=30\ \text{m}\) |
A farmer uses an existing stone wall and fencing to create a large grazing paddock for his sheep, as shown in the diagram below.
The fencing has 3-strand wiring which is also shown below.
How many kilometres of wire will be required? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(5.7\ \text{km}\)
\(\text{Fencing required}\)
\(=3\times (450 + 200 + 150 + 500 + 600)\)
\(=3\times 1900\)
\(=5700\ \text{m}=5.7\ \text{km}\)
The length of this rectangle is one and a half times its height.
The perimeter of the rectangle is 40 centimetres.
What are the dimensions of the rectangle? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(\text{Height}=8\ \text{cm}\)
\(\text{Length}=12\ \text{cm}\)
\(\text{Let}\ \ \ x\) | \(=\text{height}\) |
\(\dfrac{3}{2}x\) | \(=\text{length}\) |
\(2\times \Big(x +\dfrac{3}{2}x\Big)\) | \(= 40\) |
\(2\times \Big(\dfrac{5x}{2}\Big)\) | \(= 40\) |
\(5x\) | \(= 40\) |
\(x\) | \(= 8\) |
\(\therefore\ \text{Height}\) | \(= 8\ \text{cm}\) |
\(\therefore\ \text{Length}\) | \(=\dfrac{3}{2}\times 8\) |
\(=12\ \text{cm}\) |
Ronald places 5 identical hexagonal tiles side-by-side to make the pattern pictured below.
Each tile has a perimeter of 24 cm and is in the shape of a regular hexagon.
What is the perimeter of the large shape, in centimetres? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(64\ \text{cm}\)
\(\text{Length of 1 side}\) | \(=\dfrac{24}{6}\) |
\(=4\ \text{cm}\) |
\(\therefore\ \text{Perimeter}\) | \(=16\times 4\) |
\(=64\ \text{cm}\) |
Aragorn is fencing a paddock on his property. The total length of fencing he requires is 8.2 kilometres.
The length of the paddock is 2.8 kilometres.
Write your answer, in kilometres to one decimal place? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(1.3\ \text{km}\)
\(\text{Express as a perimeter equation:}\)
\(2\times 2.8 + 2x\) | \(= 8.2\) |
\(2x\) | \(= 8.2-5.6\) |
\(2x\) | \(= 2.6\) |
\(\therefore x\) | \(=1.3\ \text{km}\) |
\(\therefore\ \text{Side length is }1.3\ \text{km}\)
Penelope made a shape using 6 identical squares.
What is the perimeter of the shape? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(108\ \text{cm}\)
\(\text{Length of 1 side}\) | \(=\dfrac{27}{3}\) |
\(=9\ \text{cm}\) |
\(\therefore\ \text{Perimeter}\)
\(= (10\times 9) + (4\times 4.5)\)
\(= 90 + 18\)
\(=108\ \text{cm}\)
This shape is made from eight equilateral triangles and one large parallelogram.
Each side of all the small triangles is 4 cm long.
What is the perimeter of the shape? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(48\ \text{cm}\)
\(\text{Perimeter from the top left corner (clockwise)}\)
\(=12+4+4+4+4+8+4+8\)
\(=48\ \text{cm}\)
A rectangle has a length of 25 cm and a width of 20 cm.
A square has the same perimeter as this rectangle.
What is the side length of this square in centimetres? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(22.5\ \text{cm}\)
\(\text{Perimeter of rectangle}\) | \(= (2\times 25) + (2\times 20)\) |
\(=90\ \text{cm}\) |
\(\therefore\ \text{Side length of square}\) | \(=\dfrac{90}{4}\) |
\(=22.5\ \text{cm}\) |
A regular hexagon is drawn below.
5 identical hexagons are connected as shown in the diagram below.
What is the perimeter of the larger shape?
\(B\)
\(\text{Perimeter}\) | \(=\text{Number of sides}\times 5.5\) |
\(=22\times 5.5\) | |
\(=121\ \text{cm}\) |
\(\Rightarrow B\)
A shape, pictured below, is made with 5 rhombuses.
What is the perimeter of the shape?
\(C\)
\(\text{All sides of a rhombus are equal}\)
\(\text{Perimeter}\) | \(=12\times 1\) |
\(=12\ \text{cm}\) |
\(\Rightarrow C\)
A rectangular car park is shown below with a perimeter of 70 m.
What is the length of the short side \(\large x\)? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(10\ \text{m}\)
\(\text{Perimeter}\) | \(=25 + 25 + x +x\) |
\(70\) | \(=50 + 2x\) |
\(2x\) | \(=70-50=20\) |
\(\therefore x\) | \(=10\ \text{m}\) |
Andrew drew a shape as pictured below.
What is the perimeter of this shape in centimetres?
\(D\)
\(\text{Starting at the bottom left corner and}\)
\(\text{moving clockwise:}\)
\(\text{Perimeter}\) | \(= 26 + 30 + 26 + 8 + 21 + 16 + 21 + 6\) |
\(= 154\ \text{cm}\) |
\(\Rightarrow D\)
Justin connects three of his restaurant tables together to make one long table.
The view from above the tables is shown below.
Each table is 70 cm long and 50 cm wide.
What is the perimeter of the long table? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
\(520\ \text{cm}\)
The table shows the dimensions of four different rectangles in centimetres.
Rectangle | Length (cm) | Width (cm) |
1 | 9 | 5 |
2 | 10 | 8 |
3 | 14 | 2 |
4 | 18 | 10 |
Which rectangle has a perimeter of 28 centimetres?
\(A\)
\(\text{Consider rectangle 1}\)
\(\text{Perimeter}\) | \(= 2\times \text{length} + 2\times \text{width}\) |
\(= (2\times 9) + (2\times 5)\) | |
\(=28\ \text{cm}\) |
\(\therefore\ \text{Rectangle 1 has a perimeter of 28 cm.}\)
\(\Rightarrow A\)
What is the perimeter of the shape below given each square has a side length of 1 cm?
\(C\)
\(\text{Starting at the bottom right corner and}\)
\(\text{moving clockwise:}\)
\(\text{Perimeter}\) | \(=5+3+1+2+1+2+1+2+2+1\) |
\(=20\ \text{cm}\) |
\(\Rightarrow C\)