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Answer: Choice B. 5*sqrt(10)</h3>
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Explanation:
It helps to add point labels. Let's place point A at the very top point of the triangle. Then point B will be at the 90 degree angle. Point C is the far left point. Lastly, point D is on segment BC such that DC = 3.
Since BC = 8 and CA = 17, we can use the pythagorean theorem to get...
(AB)^2 + (BC)^2 = (AC)^2
(AB)^2 + (8)^2 = (17)^2
(AB)^2 + 64 = 289
(AB)^2 = 289-64
(AB)^2 = 225
AB = sqrt(225)
AB = 15
Now focus on triangle ABD and apply the pythagorean theorem again to find side AD
(AB)^2 + (BD)^2 = (AD)^2
AD = sqrt( (AB)^2 + (BD)^2 )
AD = sqrt( (AB)^2 + (BC-CD)^2 )
AD = sqrt( (15)^2 + (8-3)^2 )
AD = sqrt(250)
AD = sqrt(25*10)
AD = sqrt(25)*sqrt(10)
AD = 5*sqrt(10) .... answer is choice B
