Year 9

• Sum of interior angles

  (No.sides -2) x180
• Angles in an equilateral

  Are equal
• Angles in a triangle

  Sum to 180
• Angles on a straight line

  Sum to 180
• 2 angles in an isosceles

  Are equal
• Parallel line angles

  Sum to 180
• Co-interior angles

  Are equal
• Alternate angles

  Are rqual
• Sum of the 2 interior angles

  Equal to exterior angle of the triangle
• Opposite angles in a parallelogram

  Are equal
• Angles in a parallelogram

  Sum to 360
• Co- interior angles

  
• Alternate angles

  
• Corresponding angles

  
• Vertically opposite angles

  
• An angle in a semicircle

  Always a right angle

  
• Angle subtended at the centre or a circle

  2x the angle at the circumference

  
• Angles in the same segment

  Are equal

  
• Opposite angles in a cyclic quadrilateral

  Sum to 180

  
• 7¹² ÷ 7⁶ = 7⁶
• 6⁶ x 6⁶ = 6¹²
• (8³)⁴ = 8¹²
• 4(4⁴)⁴ = 4¹⁷
• 9p²q + 6pq = 3pq(3p + 2)
• SohCahToa

  Sin, cos, tan
• Angles in right angel

  = -SohCahToa
• Sohcahtoa letter lines

  H - hypotenuse

  O - opposite

  A - adjacent

  
• Fine 5%

  X 0.05
• Increase by 5%

  X 1.05
• Decrease by 5%

  X 0.95
• Area of a trapezium

  H/2 (top length+bottom length)
• Area of a circle

  PiR²
• Circumfrence of a circle

  2piR
• LCM

  Prime factors

  10 and 6

  2, 5 and 2, 3

  Highest factor of all powers together

  2^1 x 3^1 x 5^1 = 30
• Union - and

  
• Intersections - both

  
• Subset - a is in b

  
• Proper subset - a is in b but b has more

  
• Not a subset

  
• Complement- not A