step 1. This is a 30-60-90 triangle where the side opposite the 30° is the smallest and represented as x, the side opposite the 60 ° is the middle length at x(sqrt(3)) and the side opposite the 90° is the longest side at 2x. note: sqrt is the square root.
step 2. The ladder is 6m and is the 2x side.
step 3. The wall is across from the 60° side and is the x side.
step 4. if the 2x side is 6m then the x side is 3m.
step 5. The ladder is 3m up the side of the house.