Question

The triangular pyramid shown is made up of four congruent triangles. The length of the base is 8 inches, and the height of

the base is 6.9 inches.


6.9 in


represents the lateral area. Which


Talia is finding the lateral area of the pyramid. She says that the expression


explains whether Talia is correct and why?


PLEASE HELP


-Talia is correct. The three faces have the same area base, and the area of the base is 1/2(8)(6.9)


-Talia is correct. The lateral area can be found by approximating one large triangle, which can be found using the expression 4( 1/2 (8)6.9) )


-Talia is not correct. Only the base has an area of 1/2(8)(6.9), and three other faces have a different area.


-Talia is not correct. The lateral Area has three faces, so the expression should be 3( 1/2(8)6.9) )

Answer 1

Talia is not correct. The lateral Area has three faces, so the expression should be 3( 1/2(8)6.9) )

Explanation:

In geometry, two figures or objects are congruent if they have the same shape and size, or if one has the same shape and size as the mirror image of the other. This means that all three of the triangles that make up the faces of the triangular prism must be equal.

Since the dimensions of the base is known as 8 inches at the base and 6.9 inches high, the area of the base will be half the base times the height which is 1/2 x (8)(6.9).

The total surface area will be 3 times this area which will be,

Total surface area = 3( 1/2(8)6.9) )