Maths year 8 revision

• exterior angels add up to 360
• angels on a straight line add up to 180
• Angles around a circle add up to 360
• To find the perimeter of a rectangle, you add the length of each side.
• half the sum of the parallel sides times the height between them that is how to calculate the area of a trapezium
• Parellel is another word for the likes are drawn the same length
• a quadrilateral has four sides
• A triangle has three sides
• Perpendicular means at right angles
• A regular polygon is when all its angles are equal
• the formula for finding the volume of a cube is length x width x depth
• the radius is half the diameter
• The formula to find the perimeter of a rectangle is 2x + 2y
• The formula to find the circumference of a circle is 2πr
• The formula to find the area of a trapezium is (b1+b2)/2 x h
• The circumference of a circle is the distance around it
• The area of a circle is pi times r squared
• A right angled triangle has one angle that measures 90 degrees
• An equilateral triangle has all sides equal
• A triangle has three sides, three angles and three vertices