In triangle JKL, if JK = 15 cm, KL = 20 cm, and JL = 25 cm, what is the type of triangle? (2023)
Practice Questions
1 question
Q1
In triangle JKL, if JK = 15 cm, KL = 20 cm, and JL = 25 cm, what is the type of triangle? (2023)
Equilateral
Isosceles
Scalene
Right-angled
Since 15² + 20² = 25² (225 + 400 = 625), triangle JKL is a right-angled triangle.
Questions & Step-by-step Solutions
1 item
Q
Q: In triangle JKL, if JK = 15 cm, KL = 20 cm, and JL = 25 cm, what is the type of triangle? (2023)
Solution: Since 15² + 20² = 25² (225 + 400 = 625), triangle JKL is a right-angled triangle.
Steps: 7
Step 1: Identify the lengths of the sides of triangle JKL. They are JK = 15 cm, KL = 20 cm, and JL = 25 cm.
Step 2: Recall the Pythagorean theorem, which states that in a right-angled triangle, the square of the length of the hypotenuse (the longest side) is equal to the sum of the squares of the lengths of the other two sides.
Step 3: Identify the longest side, which is JL = 25 cm. This will be our hypotenuse.
Step 4: Calculate the square of each side: JK² = 15² = 225, KL² = 20² = 400, and JL² = 25² = 625.
Step 5: Add the squares of the two shorter sides: 225 + 400 = 625.
Step 6: Compare the sum with the square of the hypotenuse: 625 (sum of JK² and KL²) equals 625 (JL²).
Step 7: Since the equation holds true (15² + 20² = 25²), triangle JKL is a right-angled triangle.
