Egyptian British International School
Math Department
Year 8 (…..)
Name: ………………….
Geometry Formulas
Areas and Perimeters
Figure
Sketch
s
Square
Area
Perimeter
A = s2
P = 4s
w
Rectangle
A = lw
P = 2l + 2w
w
A = lh
P = 2l + 2w
s2
1
A = h(b1
2
l
h
Parallelogram
l
b1
Trapezium
s1
h
b2 )
P = s1
s2
b1 b2
b2
s1
Triangle
h
b
s2
1
A = bh
2
P = s1
s2
b
Volumes and Surface Areas of Three- Dimensional Figures
Figure
Rectangular
Solid
Sketch
Volume
Surface Area (S)
V = lwh
S = 2lh + 2wh + 2wl
V = s3
S = 6s2
h
w
l
Cube
s
s
s
Equation of straight line :
y = mx + c
where m is the gradient and c is the y-intercept.
Gradient