Work out how many people are in an office, given the ratio of females to males and what proportion wear glasses.
Polygons
A polygon is a 2-dimensional many sided shape. If all the sides are the same length it is a regular polygon, if not it is an irregular polygon. A polygon is usually thought of as a convex shape (roughly circular), but they don't have to be, they can fold in on themselves and have intersecting... Continue Reading →
Exam Question Technique
Here is question 18 from the AQA 3F June 2017 paper: The first thing to notice is this question is worth a whopping 5 marks and there is that tell-tale sentence 'You must show your working.', so it is going to require some thought and thorough working out. Before committing anything to paper have a... Continue Reading →
More on quadratics
Why does the general method Factorising quadratics, work? We are trying to factorise a general quadratic ax²+bx+c [1] into the form (dx+e)(fx+g). Multiplying this out gives: dx(fx+g)+e(fx+g) [2] dfx²+dgx+efx+eg [3] dfx²+(dg+ef)x+eg [4] If a = df, b = dg+ef and c = eg, then equation [1] is same as equation [4]. So ac can be... Continue Reading →
Factorising quadratics
When factorising quadratics of the form x²+bx+c, the usual procedure is to write it like this: (x+..)(x+..) and then think of 2 numbers which multiply together to give c and add up to give b. So, for example: x²+x-12 factorises to (x+4)(x-3), because 4 * -3 = -12 and 4-3=1. Possible combinations which multiply together... Continue Reading →
A trick for squaring numbers near 50
Did you know, there is a neat trick for working out the square of numbers near 50? Lets say, you want to find 53² Start with 2500 (the square of 50), add on 100 times the difference between your number and 50 (3x100 = 300 in this example), and finally add on the square of... Continue Reading →
Revision Technique
An effective revision technique can make all the difference. Here are my handy hints: Get yourself organised with a folder or notebook for each subject. Condense your notes into well ordered, easy to read and colourful notelets. Don't put too much information on each notelet, they should contain key facts to jog your memory. Highlight... Continue Reading →
Southville Maths Tutor 