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Find the value of AB,BC,and BD IN THE GIVEN FIGURE WHICH IS AD = 16cm and CD= 9cm |
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Answer» Given :
To find :
Solution :
★(Hypotenuse)²=(perpendicular)²+(base)²
→ (AC)² = (AB)² + (BC)² → (16 + 9)² = AB² + BC² → (25)² = AB² + BC² → AB² + BC² = 625 ---(i)
→ (AB)² = (BD)² + (AD)² → AB² = BD² + (16)² → AB² - BD² = 256 -----(ii)
→ (BC)² = (DC)² + (DB)² → BC² = (9)² + DB² → BC² - DB² = 81 -----(iii) Subtract equations (ii) & (iii) the equations → AB² - BD² - (BC² - DB²) = 256 - 81 → AB² - BD² - BC² + DB² = 175 → AB² - BC² = 175 ------(iv) Add equations (i) and (iv) → AB² + BC² + AB² - BC² = 625 + 175 → 2AB² = 800 → AB² = 800/2 → AB = √400 = 20 cm Put the value of AB in eqⁿ (i) → AB² + BC² = 625 → (20)² + BC² = 625 → 400 + BC² = 625 → BC² = 625 - 400 → BC = √225 = 15cm Put the value AB in eqⁿ (ii) → AB² - BD² = 256 → (20)² - BD² = 256 → 400 - BD² = 256 → BD² = 400 - 256 → BD = √144 = 12 cm •°• AB = 20cm, BC = 15cm & BD = 12cm |
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