Consider the rectangle ABCD. Point E is the midpoint of DC and point F is the midpoint of BC. If points A, E, and F are joined to form a triangle, what is the ratio of the area of triangle AEF to the area of triangle ABF.
Q. Consider the rectangle ABCD. Point E is the midpoint of DC and point F is the midpoint of BC. If points A, E, and F are joined to form a triangle, what is the ratio of the area of triangle AEF to the area of triangle ABF.
Identify Properties: Identify the properties of the points E and F on rectangle ABCD. Since E and F are midpoints of DC and BC respectively, DE=EC and BF=FC.
Consider Triangles: Consider the triangles AEF and ABF. Triangle AEF is formed by joining points A, E, and F, and triangle ABF is formed by joining points A, B, and F.
Observe Common Height: Observe that triangles AEF and ABF share a common height from point A perpendicular to line BF. The base of triangle AEF is EF, and the base of triangle ABF is BF. Since F is the midpoint of BC, BF is half of BC.
Calculate Length of EF: Calculate the length of EF. Since E is the midpoint of DC, and DC is equal to BC in a rectangle, EF is half of BC. Therefore, EF=21BC.
Compare Areas of Triangles: Compare the areas of triangles AEF and ABF. The area of a triangle is 21×base×height. Both triangles share the same height, so the ratio of their areas will be the ratio of their bases.
Calculate Ratio of Bases: Calculate the ratio of the bases EF and BF. Since EF=21BC and BF=21BC, the ratio BFEF=21BC21BC=1.
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