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Find the area of ΔLKJ

Find the area of ΔLKJ-example-1
User Alexzander
by
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1 Answer

8 votes

9514 1404 393

Answer:

D. 37.5 square units

Explanation:

There are a couple of ways to figure this.

1. The altitude KM is the geometric mean of the segment lengths ML and MJ

KM = √(ML·MJ)

ML = KM²/MJ = 36/8 = 4.5

Then LJ = 4.5 +8 = 12.5, and the area of the triangle is ...

A = (1/2)bh

A = (1/2)(12.5)(6) = 37.5 . . . square units

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2. Triangle LKM is similar to triangle KJM. The scale factor is ...

KM/JM = 6/8 = 3/4

Then the area of triangle LKM is (3/4)² = 9/16 of the area of triangle KJM.

The total area is ...

Area of LJK = (area of KJM)×(1 + 9/16)

= (1/2)(8)(6)(25/16) = 75/2 = 37.5 . . . square units

User Kiren S
by
4.0k points