Maths Revision
 Created by: Zaid
 Created on: 171112 12:33
Angle Relationships:
Vertically opposite angles are equal
Corresponding angles are equal
Alternate angles are equal
Adjacent angles add up to 180 degrees
Interior angles add up to 180 degrees
Base angles in an isosceles triangle are equal
Angles that add up to 180 degrees are suplementry
Angles that add up to 90 degrees are complementy
Exterior Angles:
They are the angles the shape has after the sides are extended. polygons exterior angles always add up to 360 degrees so, 360/the number of sides equals the exterior angle.
On a triangle the exterior angle is the sum of the interior angles of the other two vertices.
Interior Angles:
If you know the exterior angle of the poygon then the interior angle is 180the exterior angle because exterior angle & the interior angle are on a straight line.
To find the sum of the angles inside a polygon we cut the polygon into triangles. the cutting lines must not cross. Working: if we cut the pentagon into 3 triangles. the anglesum in each triangle is 180 degrees. therefore the anglesum of the pentagon is 3 x 180 = 540 degrees
Vocabulary:
Acute angle between 0 and 90 degrees
Right angle 90 degree angle
Obtuse angle between 90 and 180 degrees
Straight 180 degrees
Reflex angles over 180 degrees
1. Number and Algebra.
Multiplying and dividing negative numbers –
E.g.
2*+4
2*4=8, and  * + is equivalent to . So 2*+4=8
6*3
6*3=18 and  is equivalent to +, so 63 =+8
+6*4/2
+6*4= 24, 24/2=+12
Key

 = 

 = +
 /  = +
= +
+= 
1.
a) 7+8 = 1
j) 5+4—7=
4.
a) +2*3= 6
o) 2*+4*2= 16
HCF and LCM 
E.g.
HCF stands for highest common factor
LCM stands for lowest common multiple
Find the LCM of two numbers
a) 3 and 7 = 21
b) 6 and 9 = 18
A factor is a smaller number that divides exactly into a larger number.
e.g. 2, 3 and 4 are all factors of 12
Find the HCF of two numbers
a)15 and 21 = 3
b) 16 and 24 = 8
Powers and roots –
E.g.
4”3” = 4*4*4 = 64
( Most calculators have a squaring button )
/12.25 = 3.5
(Depending on your calculator, sometimes you type the square root before the number, and sometimes the number comes first. Make sure you can use your calculator.)
Prime Factors
E.g.
Find the prime factors of 18.
Using a prime factor tree, split 18 into 3*6 and 6 into 3*2.
So, 18 = 2*3*3=2*3”2”
Note that 2*”3” is called index form.
Find the prime factors of 24.
Using the divide method:
2/24
2/12
2/6
3/3
1
So 24=2*2*2*3=2”3”*3
Sequences –
StartWrite down 3Add on 5Write answerMore than 40yes STOP.
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