Activities-Pythagoras theorem problems

'Solution in some special right angled triangle whose angle ratio 1:2:3 that is 30-60-90 has their sides ratio 1: $${\sqrt3}$$ :2
 * 1) In Right angled ∆ABC,∟BAC= 90°,∟B: ∟C = 1:2 andAC= 4cm.calculate thelenght of BC

in ▲ABC, BC = 2. AC

BC = 2.4

BC = 8 cm


 * 1) A door of width 6 mt has an archabove it having aheight of 2 mt, find the radius if the arch
 * 2) The sides of a right angled triangle are in an AP. Show that sides are in ther ratio 3:4:5