The base of a 20-foot ladder is placed 12 feet from a building. How far up on the building does the ladder reach?16 ft8 ft23 ft4 ft

Answer:answer is:16 feet.Step-by-step explanation:We are given that:The base of a 20-foot ladder is placed 12 feet from a building.Now we re asked to find how far up on the building does the ladder reach?i.e. we can consider a right angled triangle such that the base is given to be 12 feet.the length of hypotenuse is given to be= 20 feet.Now we are asked to find the height of a right angled triangle.Let us consider ΔABC.such that ∠B=90°, BC=12 feet, AC=20 feetNow we can  use pythagorean theorem to find out the length of side AB.[tex]AC^{2}=AB^{2}+ BC^{2}\\\\AB^{2}=AC^{2}-BC^2\\\\AB^2=(20)^2-(12)^2\\\\AB^2=400-144\\\\AB^2=256\\\\AB=16[/tex]Hence, ladder is 16 feet above the ground level.