Question
In ∆ABC , G is the centroid , AB = 18 cm, BC= 24 cm
and AC = 30 cm , find GD, where D is the mid-point of BC?Solution
If AD is the median, then we know, AB² + AC² = 2{AD² + (BC/2)²} or 182 + 302 = 2{AD 2 + (24/2) 2 } or 324 + 900 = 2{AD 2 + 144} or 1224/2 = AD 2 + 144 or 612 = AD 2 + 144 or AD 2 = 612 – 144 = 468 or AD = 6√13 = 6√13 Now G divides median in 2:1 so GD = 1/3 of AD = 1/3 of 6√13 = 6√13/3cm
More Geometry Questions
√256 * 3 – 15% of 300 + ? = 150% of 160
(5.6 + 2.4 + 13.8 – 2.8) × 5 = ? × (12.5 – 7.5)
Solve: 3/4÷2/3
(292 – 141) ÷ 5 + (40 ÷ 2) + 23 = ?
(26)2 = {(20% of 40% of 18200) ÷ ?} × 1664 ÷ 128
- What will come in place of (?) in the given expression.
(18.5 × 2) + (3.5 × 4) = ? What will come in the place of question mark (?) in the given expression?
48 X 2.5 + 20% of 150 = ? + 166
166/? = √576 - 3.25
[(36 × 15 ÷ 96 + 19 ÷ 8) × 38] = ?% of 608
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