



 
Hi Jade, In my diagram the length of the line segment AB is 60 ft and the measure of the angle ABC is 45^{o}.
Use the sine and cosine of 45^{o} to find the length of the line segments BC and CA and find the area of the triangle ABC. The volume of dirt in the embankment as it exists now is the area of this triangle times the length of the embankment, 200 ft. What is this volume? The embankment is to be cut down to the line segment BD where the measure of the angle DBC is 30^{o}. Again use trigonometry to find height of the new embankment CD. Use this to calculate the area of the triangle DBC and then the volume of dirt in the new embankment. How much dirt was removed? Penny  


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