In triangle JKL, if angle J = 90 degrees and JK = 15 cm, KL = 20 cm, what is the
Practice Questions
Q1
In triangle JKL, if angle J = 90 degrees and JK = 15 cm, KL = 20 cm, what is the length of JL? (2022)
10 cm
12 cm
15 cm
25 cm
Questions & Step-by-Step Solutions
In triangle JKL, if angle J = 90 degrees and JK = 15 cm, KL = 20 cm, what is the length of JL? (2022)
Step 1: Identify the triangle JKL where angle J is 90 degrees. This means it is a right triangle.
Step 2: Note the lengths of the sides: JK = 15 cm (one leg) and KL = 20 cm (the hypotenuse).
Step 3: Use the Pythagorean theorem, which states that in a right triangle, the square of the hypotenuse (KL) is equal to the sum of the squares of the other two sides (JK and JL).
Step 4: Write the formula: KL² = JK² + JL².
Step 5: Substitute the known values into the formula: 20² = 15² + JL².
Step 6: Calculate 20² and 15²: 20² = 400 and 15² = 225.
Step 7: Rewrite the equation with these values: 400 = 225 + JL².
Step 8: To find JL², subtract 225 from both sides: JL² = 400 - 225.
Step 9: Calculate the result: JL² = 175.
Step 10: To find JL, take the square root of 175: JL = √175.
Step 11: Calculate the square root of 175, which is approximately 12.25 cm.
