To find "t" you HAD to draw a graph, unless you can mentally visualise these things, which i doubt many can do.
You would plot both points A and B onto the graph, and then because we are given that the length is the same as AB root(41) you have to assume it is the same distant away from A as it is To B - if that makes any sense???
That means it has to be vertically onto of B and double the original height, so basically an isosceles triangle.
I thought that question was actually quite stupid, for one mark it needed quite alot of working.
For the Graph Intersection question, How many marks are you likely to lose if you drew the x^2(7-x) graph, the wrong way so upside down, and how many marks are likely to be lost on the last section if you didnt give a correct y co-ordinate for 4 - 2(root(3))???