



 
Hi Carla, The angle between the slant face and the base is angle PQE. Triangle PQE is a right triangle, QE = 20 cm and PQ = 4 cm so cos(PQE) = 4/20 = 1/5. Hence the measure of angle PQE is cos^{1}(1/5). A similar method can be used to find the measure of the angle PAE, the angle between the slant edge and the base by first applying Pythagoras theorem to triangles PAQ and EPA. Penny  


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