The perimeter of a right triangle is 24 centimeters. Three times the length of the longer leg minus two times the length of the shorter leg exceeds the hypotenuse by 2 centimeters. What are the lengths
of all three sides?
Answers
Given info : The perimeter of right angled triangle is 24 cm. also 3b - 2b = h + 2 cm , where b is longer leg , a is shorter leg and h is hypotenuse.
To find : the lengths of all sides of triangle are...
solution : perimeter of triangle = a + b + h
⇒24 = a + b + h ....(1)
from question, 3b - 2a = h + 2 ...(2)
from Pythagoras theorem,
h² = a² + b² ...(3)
from equations (1) and (2), we get,
3b - 2a = 24 - a - b + 2
⇒4b - a = 26 ....(4)
from equations (1) and (3) we get,
(24 - a - b)² = a² + b²
and from eq (4) we get,
(24 - 4b + 26 - b)² = (4b - 26)² + b²
⇒50² + 25b² - 500b = 16b² + 676 - 208b + b²
⇒8b² - 292b + 2500 - 676 = 0
⇒8b² - 292b + 1824 = 0
after solving it using quadratic formula you get, b = 8, 57/2
let's take b = 8
then, a = 4b - 26 = 4 × 8 - 26
= 32 - 26 = 6
and h = √(8² + 6²) = 10
Therefore the lengths of sides are 10, 8, 6