Question

A rectangular pyramid has a height of 10 meters. The base measures 8 meters in length and 12 meters in width. Two different triangular cross sections are formed through the vertex and perpendicular to the base. What is the difference in the areas of the cross sections?

If someone is able to help me fast that would be great!!!

Answer 1

Difference in the areas of the cross sections = 20 m²

Explanation:

(i) Area of the first cross section

base,b = 8 m, height,h = 10 m

Area of the triangle =
`(1)/(2)` bh

area =
`(1)/(2)` (8) (10)

area = 40 m²

(ii) Area of the second cross section

base,b = 12 m, height,h = 10 m

Area of the triangle =
`(1)/(2)` bh

area =
`(1)/(2)` (12) (10)

area = 60 m²

Difference in the areas of the cross sections = 60 - 40 = 20 m²