ABC is a right angle triangle at B, D is a point on AC such that DC = 8cm, AD = 34cm and BD = 17cm, find the area of ∆BDC
Answers
Answer:
Step-by-step explanation:
area of triangle=1/2 * base * height
1/2*34+8*17
357
Given : ABC is a right angle triangle at B, D is a point on AC such that DC = 8cm, AD = 34cm and BD = 17cm,
to find : Area of triangle ∆BDC
Solution:
Lets draw BE ⊥ AC
BE = x cm
DE = y cm
BE² + DE² = BD²
=> x² + y² = 17²
=> x² + y² = 289
BE² + CE² = BC²
=> x² + (CD + DE)² = BC²
=> x² + (8 + y)² = BC²
=> x² + y² + 16y + 64 = BC²
BE² + AE² = AB²
=> x² + (AD - DE)² = AB²
=> x² + (34 - y)² = AB²
=> x² + y² - 68y + 1156 = AB²
AB² + BC² = AC²
=> x² + y² - 68y + 1156 + x² + y² + 16y + 64 = (AD + CD)²
=> 2( x² + y²) -52y + 1220 = (34 + 8)²
=> 2(289) - 52y + 1220 = 42²
=> 1798 - 52y = 1764
=> 52y = 34
=> y = 34/52
=> y = 17/26
x² + y² = 289
=> x ² + (17/26)² = 289
=> x = 16.987
Area of ∆BDC = (1/2) * DC * BE
= (1/2) * 8 * 16.987
= 67.95 cm²
Area of ∆BDC = 67.95 cm²
Learn more:
In a right angled triangle the hypotenuse is 10 cm more than the ...
https://brainly.in/question/8992388
in a triangle pqr angle Q is a right angle and QT is a perpendicular ...
https://brainly.in/question/13149578