Question

how do you find the area of composite shapes?

Answer 1

It depends on the shape, but use the surface area formulas, but remove the parts that are covered by the other solid. For instance:

Normally, the formula for surface area is a cylinder:
\[SA = 2πr^{2} + 2πrh\]
Surface area for a cone:
\[SA = πr^{2} + πrl\]
However, in this drawing the base of the cone and one of the bases of the cylinder are gone. Therefore, you modify and combine the formulas.
\[TA = πr^{2} + πrl + 2πrh\]
See the parts that are removed?