P is 2km from Q and R lies on the perpendicular bisector at the link between P and Q and distance from P to R is 3 km. 1. Find Length for Plan 1 2. " " " Plan 2 3. " " " Plan 3 4. " " " Plan 4 5. Decide which plan would be used if minimizing the cost. http://www.jeack.com.au/~dngo/maths.bmp are the diagrams. i solved question 1 + 2. just need help from 3 - 5. if some people do not wish to look at the picture i will give a visual description in words. diagram 3 = is in a Y shape. the distance in the middle from P to Q is x. and the stroke down which is R, opposite sides of R is x. so alltogether there are 3 unknowns. diagram 4 = is in a Y shape, P to Q is equal which has sides b. the distance in the middle from P to Q is 120. opposites of R is 120. i suggest you can please look at the web link http://www.jeack.com.au/~dngo/maths.bmp thanks.