QuestionWatch VideoShow ExamplesA 40 foot ladder is set against the side of a house so that it reaches up 24 feet. If Lily grabs the ladder at its base and pulls it 4 feet farther from the house, how far up the side of the house will the ladder reach now? (The answer is not 20ft.) Round to the nearest tenth of a foot.
Q. QuestionWatch VideoShow ExamplesA 40 foot ladder is set against the side of a house so that it reaches up 24 feet. If Lily grabs the ladder at its base and pulls it 4 feet farther from the house, how far up the side of the house will the ladder reach now? (The answer is not 20ft.) Round to the nearest tenth of a foot.
Identify Problem: question_prompt: How far up the side of the house will the ladder reach now after being pulled 4 feet farther from the house?
Original Triangle: Original ladder position forms a right triangle with the house and ground. The ladder is the hypotenuse, 40 feet. The height reached is one leg, 24 feet. We need to find the original distance from the house, which is the other leg.
Pythagorean Theorem: Use Pythagorean Theorem: a2+b2=c2, where c is the ladder length, a is the height reached, and b is the original distance from the house. Plug in the known values: 242+b2=402.
Calculate Original Distance: Calculate the original distance from the house: 242+b2=402, so 576+b2=1600. Subtract 576 from both sides to get b2=1600−576.
Find Original Distance: Continue calculation: b2=1600−576, so b2=1024. Take the square root of both sides to find b: b=1024.
Calculate New Distance: Find the original distance from the house: b=1024, so b=32 feet.
New Triangle: Lily pulls the ladder 4 feet farther from the house, so the new distance from the house is 32+4=36 feet.
Calculate New Height: Now we have a new right triangle with the ladder still as the hypotenuse (40 feet) and the new distance from the house (36 feet). We need to find the new height reached using the Pythagorean Theorem: a2+362=402.
Calculate New Height: Calculate the new height reached: a2+362=402, so a2+1296=1600. Subtract 1296 from both sides to get a2=1600−1296.
Final Height: Continue calculation: a2=1600−1296, so a2=304. Take the square root of both sides to find a: a=304.
Final Height: Continue calculation: a2=1600−1296, so a2=304. Take the square root of both sides to find a: a=304. Find the new height reached: a=304, so a≈17.4 feet. Round to the nearest tenth of a foot.