For a triangle:
Area = (1/2)·base·height
You are given the Area (144 mi2) and the height (8 mi). Plug those values in and solve for the base.
144 = (1/2)·base·8
144 = 4·base
36 mi = base
Philip P.
tutor
The equation is Area = (1/2) x base x height. The problem gives the area = 144 and the height = 8, so we get 144 = (1/2) x base x 8 = 4 x base, not 8 x base. 8 x base would be the area of the whole rectangle; the area of the triangle is half that, 4 x base. Only thing I can think of would be if 144 is the area of the rectangle not the triangle; otherwise 36 is the correct answer.
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11/20/18
Michael G.
Thank you. I'll keep you posted on follow up.
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11/20/18
Michael G.
Thank you for your response. That was the answer my daughter selected; however, her teacher provided this response: "The question already states the area of the triangle as 144 square miles and the height is 8 miles. 144= 8 X height is the equation - divide both sides of the equation by 8. height = 18 Please picture a rectangle bisected by a diagonal to form two triangles, each with an area of 144 square miles.. The base of each triangle and the height of each triangle with be the same numbers for both triangles, but the area of the rectangle is both areas added together." What are we missing? I still believe the correct answer is 36. Your thoughts?11/20/18