Answer:
AD = 2.4
Step-by-step explanation:
All of the triangles in this figure are similar, so their corresponding sides have the same ratios.
The short side of ΔABD is 3/5 of the hypotenuse, which is 4.
AD/AB = CA/CB . . . . = short side/hypotenuse
AD = AB(CA/CB) = 4(3/5) = 2.4
The length of AD is 2.4 units.
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You can also go at this in terms of area.
A = 1/2bh = 1/2(3)(4) = 1/2(5)(AD) ⇒ AD = 12/5 = 2.4
