What is the surface area of a triangular pyramid if the base is 12 by 12 and each triangle is 12 by 15?

504 cm squared

Step-by-step explanation:

To find the surface area, find the area of the square base and add it to the area of each triangle face.

Find the area of the base by multiplying base length by base length.

Here the base is 12 x 12 = 144.

Find the area of each triangle face by multiplying 1/2 * b*h.

Here the area is 1/2 * 12 * 15 = 90. Since there are 4 faces, the total area is 4 * 90 = 360.

Together the surface area is 360 + 144 = 504.

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.

is there more to this question?