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3 years ago

Find the volume of a regular tetrahedron whose altitude measures 10cm.

1 answer:

5 0

H = 10 cm, a - edge;
V = 1/3 a²√3 / 4 * h
h² = ( 2/3 * a√3 / 2 )² + a²
100 = a²/3 + a²
100 = 4 a² / 3
a² = 75
a = √75
a = 5 √3 cm
V = 1/2 * 75√3 / 4 * 10 = 250√3 / 4 = 62.5√3 cm³ ≈ 108.25 cm³

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borishaifa [10]

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Step-by-step explanation:

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3 years ago

Solve for x:a(a²+b²)x²+b²x-a

m_a_m_a [10]

Answer:

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Step-by-step explanation:

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2. Solve for x

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4 years ago

zzz [600]

Answer:

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Step-by-step explanation:

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In trapezoid ABCD, BC and AD are the diagonals.

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8 0

3 years ago

Someone please help me answer this!!

Liula [17]

Answer:

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Step-by-step explanation:

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3 years ago

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VLD [36.1K]

Answer:

Step-by-step explanation:

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3 years ago

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