the perimeter og a right _ angled triangle is 48 centimeters, and its area is 96 square centimeters. length of hypotenuse is 20 cm.
what is the length of the perpendicular sides?
Answers
Correct Question :
The perimeter of a right angled triangle is 48 cm , and its area is 96 cm² . Length of its hypotenuse is 20 cm . What is the length of the perpendicular sides ?
Solution :
Let , In a right angled triangle ,
- B ⇔ Base
- P ⇔ Perpendicular
- H ⇔ Hypotenuse
Perimeter of a right angled triangle is sum of all its sides ,
➳ Per. = B + P + H
- Hypotenuse , H = 20 cm
➳ Per. = B + P + 20
- But it is given Per. = 48 cm , so ,
➳ 48 = B + P + 20
➳ B + P = 28
➳ P = 28 - B ... (1)
Area of a right triangle is ,
where ,
- h denotes height = perpendicular (P)
- b denotes base = Base (B)
➠ A = ¹/₂ × B × P
- Given , Area of the triangle is 96 cm²
➠ 96 = ¹/₂ × B × P
➠ BP = 192
Sub. (1) ,
➠ B ( 28 - B ) = 192
➠ 28B - B² = 192
➠ B² - 28B + 192 = 0
➠ B² - 12B - 16B + 192 = 0
➠ B ( B - 12 ) - 16 ( B - 12 ) = 0
➠ ( B - 12 ) ( B - 16 ) = 0
➠ B = 12 ; 16 cm
Sub. B value in (1) ,
➠ P = 28 - (12) or 28 - (16)
➠ P = 16 or 12
➠ P = 16 ; 12 cm
So ,
Base of the triangle = 12 or 16 cm
Perpendicular of the triangle = 16 or 12 cm
Length of the perpendicular sides are 12 and 16 cm respectively