Jeremy is building a model of a square project. The side length of the square base is 12 inches and the slant height of the pyramid is 20 inches. What is the surface area of the model pyramid?

Question

anonymous · Answer

can someone help me out real quick please

anonymous · Answer

how many triangular faces are on the pyramid?

what does surface area mean?

what is the area of a square?

what is the area of a triangle?

anonymous · Answer

please answer these questions

anonymous · Answer

a. i think four
b. isnt that like the bottom part of the pyramid?
c.and the area is that the 20 inches?

goformit100 · Answer

Yes it is corect.

anonymous · Answer

a. a pyramid with a square base has 4 triangular faces
b. the surface area of a object is the sum of area of all faces
in this case, the surface area of the pyramid would be the area of the square base plus the area of the 4 triangular faces

c. no
d. blank

anonymous · Answer

the area of a square can be given by the equation
$$A_\square= s^2 = s * s$$
the area of a triangle can be given by the equation
$$A _\triangle = 1/2* b *h$$

anonymous · Answer

any questions or comments?

anonymous · Answer

so for the area of the square it would be..
A=12^2=12*12?

anonymous · Answer

yes
12*12 =?

anonymous · Answer

i typed it in 2 ways in case you didnt know that the 2 meant

anonymous · Answer

oh okay so it would be 12*12=144?

anonymous · Answer

yes the area of the square base would be 144  inches

anonymous · Answer

sorry inches squared

anonymous · Answer

or 12^2=144inches.. oooh okay! and for the last one it would be 1/2*12*20?

anonymous · Answer

120 inches?

anonymous · Answer

yes the area of the triangular face would be 120 in^2

now since there are 4 triangular faces,

so the total area of the triangular faces would be?

anonymous · Answer

um... 264..??? i added the 120 and 144

anonymous · Answer

ok what you have so far is the area of 1 triangular face and the square base

you're missing 3 triangular faces

anonymous · Answer

4 triangular faces + square base

120+120+120+120+144 = ?

anonymous · Answer

oh 624?

anonymous · Answer

do you understand what surface area means now?

anonymous · Answer

um.. i think so :) Thank you i appreciate it!

anonymous · Answer

also i suggest memorizing the equation for the area of the triangle and the equation for the area of hte square

anonymous · Answer

Okay i will do that and write it down also :) thanks