



 
Hi JaninI hope there are ends on this trough, otherwise all the water will run out. The volume of water in the trough is 15 gallons or 15 × 321 = 3465 cubic inches. The length of the trough is 11 × 12 = 132 inches and the volume of the water is the area of the triangular crosssection times the length so the area of the triangular crosssection is
I drew a diagram of the triangular crosssection of the trough. The area of the triangular crosssection of the water is b × d so
The triangle DCB is an isosceles right triangle so the measure of the angle BCD is 45 degrees. The triangle ABC is also a right triangle and hence, since the measure of the angle BCA is 45 degrees triangle ABC is isosceles also. What does that tell you about b and d? Penny
 


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