Perimeter and area of a shape
By Yejin and Amy
P=40cm
A=100cm
To find out the area and perimeter of a square you have to do….
10cm
Area: Length x Width
Perimeter: Length + Width + Length + Width
Eg. P=10+10+10+10=40cm A=10x10=100cm
We did 100cm because we times cm by itself, which makes cm
12cm
To find out how to calculate the area and perimeter of a rectangle you have to do…..P=40cm
A=96cm8cm
Area: Length x Width
Perimeter: Length + Width + Length + Width
Eg. 8+12+8+12=40cm A=8x12=96cm
We did 96cm because we times cm by itself, which makes cm
To find out how to calculate the area and perimeter of an isosceles triangle you have to do…..
10cm
10cmArea: height x breadth divide by 2
Why?
Because there are 2 right angled triangles and each has an area of 25cm
Eg. P= 10+11+11= 32cm A=10x10 divide by 2=50cm
We did 50cm because we times cm by itself, which makes cm
A square number is a number that times it by it self , for example….
8 =8 x8 9 = 9 x 9 10 = 10 x 10 11 = 11 x 11
Pythagoras Theorem
Pythagoras was a famous mathematician. It is called Theorem because it is not 100 percent proved to be right.
To see how to do it click…
Example
Pythagoras Theorem
16cm 4cm
3cm 9cm
25cm
5 cm
Circumference of a circle and area of a circle
To get perimeter (called circumference) of a circle you have to do..
D x pi = Circumference of a circle Pi= 3.142To get area of a circle you have to do….R x pi= area of a circle.R= radiusD= diameter
Circumference of a circle and area of a circle
Circumference of a circle= Dxpi
Area of a circle= r x pi
diameter
radius
WRONG!!!!
Quiz!!!!
What do you have to do to get area?
A: Length x width
B:Width x Width
CORRECT!!!!
Quiz
What are the three first numbers of pi?
A: 3.14
B: 3.24
WRONG!!!
CORRECT!!
Quiz!!
What do you have to do to get the circumference of a circle?
A: Dxpi
B: R xpi
Correct!!
Wrong!!
Last quiz
What do you call the area outside a circle?
A: are of a circle
B: don’t know
C: circumference
D: perimeter of a circle
Correct!!
Wrong!!
Half Right Half Wrong!!
Thank you!!!And WELL DONE!!!