A pyramid of volume 344 square units is sliced into two pieces by a plane parallel to the base of the pyramid and 10 units away from the plane of the base. The volume of the resulting frustum is 301 square units. What was the height of the original pyramid?

80 units

Step-by-step explanation:

v = 1/3 bh

v₁ = 1/3 * b * h₁ = 344

v₂ = 1/3 * b * h₂ = 301

v₁ / v₂ = h₁ / h₂ = 344 / 301

h₂ = h₁ - 10

h₁ / (h₁ - 10) = 344 / 301

344 * (h₁ - 10) = 301 * h₁

344* h₁ - 3440 = 301 * h₁

43 * h₁ = 3440

h₁ = 80

b. an equilateral triangle inscribed in a circle

step-by-step explanation:

we are given the figure of two circles having a triangle inside.

now, we know that,

"when a figure is lying inside an another figure, then the outside figure is known as circumscribed figure and the figure lying inside is referred to as the inscribed figure".

as we see that, the circles are containing the triangle completely.

thus, the circles are the circumscribed figures and the triangle is the inscribed figure.

hence, we get, 'an equilateral triangle is inscribed in a circle'.