23a 13 for the x coordinate               Award one mark 23b. 15 for the y coordinate                  Award one mark If the answer is written as (15,13) award one mark. Accept unambiguous answers written on the diagram rather than in the answer box. Suggested Method: A coordinates grid without the axes labelled is a favourite with the test writers – seldom are the axes numbered and children should have come across plenty of this type of problem before. The first thing to realise is that the x axis coordinate is written first. The next thing to do is work out the values on the points between A and B. At this stage it might be a good idea to draw in the horizontal and vertical lines. The x coordinate at A is 10. The x coordinate at B is 22. There are three other points. As they are equally spaced they must go up in threes: i.e. 10   13   16   19   22. The y coordinate at A is 10. The y coordinate at B is 30. There are three other points. As they are equally spaced they must go up in fives: i.e. 10   15   20   25   30. The coordinates for point C are (13,15) Question 23 Paper A 2011 Answer 23 Paper A 2011