Question

The surface area of this pyramid is 189cm2 The area of the square base is 49cm2. What is the area of one triangular face of the lateral surface?

Answer 1

Remember that the area formula is/
1/3(b*h)

Answer 2

You have a square base for the pyramid. This means that there will be 4 triangular face joined together to make the pyramid, if you get what I mean.

Therefore, subtract the area of the square base from the area of the pyramid to get the area of the 4 triangular faces.

Then, just divide by 4 to get the area of only one of them.