Final answer:
The exact lengths of the two legs AC and BC of an isosceles right triangle with a hypotenuse of 18 feet are 9√2 feet each. Using the Pythagorean theorem, we calculate the area of the triangle to be 81 square feet when rounded to the nearest square foot.
Step-by-step explanation:
To find the lengths of the other two sides, AC and BC, of isosceles right triangle ABC with hypotenuse AB of length 18 feet, we employ the Pythagorean theorem. Since triangle ABC is an isosceles right triangle, sides AC and BC are equal, and we can denote their lengths as 'x'. Applying the theorem, we have:
x² + x² = 18²
2x² = 18²
x² = (18²) / 2
x² = 324 / 2
x² = 162
x = √162
x = 9√2 feet
The exact lengths of both AC and BC are 9√2 feet.
To calculate the area of triangle ABC, we use the formula for area of a right triangle, which is (base * height) / 2. In this case, base and height are equal (AC = BC), so it simplifies to:
Area = (AC * AC) / 2
Area = (9√2 * 9√2) / 2
Area = (81 * 2) / 2
Area = 162 / 2
Area = 81 square feet
To the nearest square foot, the area of triangle ABC is 81 square feet.