Question

a right angled triangle has sides which are 2cm and 7cm shorter than its hypotenuse find the length of the hypoenuse

Answer 1

Answer:

The length of the hypotenuse side is (9 + 2·√7) cm

Step-by-step explanation:

The given parameters of the triangle are;

The type f triangle = Right triangle

The length of the sides 2 cm and 7 cm shorter than the hypotenuse

Let 'h' represent the length of the hypotenuse side of the triangle, in centimeters we have;

The length of one side of the right triangle = (h - 2) cm

The length of the other side of the right triangle = (h - 7) cm

By Pythagoras's theorem, we have;

h² = (h - 2)² + (h - 7)²

Using search function on the internet, we have;

h² = (h - 2)² + (h - 7)² = 2·h² - 18·h + 53

∴ h² = 2·h² - 18·h + 53

∴ 2·h² - 18·h + 53 = h²

h² - 18·h + 53 = 0

53 is a prime number, therefore, by the quadratic formula, we have;

h = (18 ± √((-18)² - 4×1×53))/(2 × 1)

h = 9 + 2·√7 cm ≈ 14.29 cm or h = 9 - 2·√7 ≈ 3.71

However, given that one of the side is 7 cm shorter than the hypotenuse, for all the sides to remain positive, we have h = 9 + 2·√7 cm ≈ 14.29 cm , because for h ≈ 3.71 cm, we have;

The length of the other side = (h - 7) cm ≈ (3.71 - 7) cm ≈ -3.29 cm which is not possible for a real triangle

Therefore, the length of the hypotenuse side, h = 9 + 2·√7 cm ≈ 14.29 cm.