Questions on Geometry: Triangles answered by real tutors!

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Question 155020: The hypotenuse of a right triangle is twice as long as the shortest side. The third side is 10√3 cm long. Find the length of the hypotenuse.: The hypotenuse of a right triangle is twice as long as the shortest side. The third side is 10√3 cm long. Find the length of the hypotenuse.
Answer by nerdybill(1049) About Me  (Show Source):
You can put this solution on YOUR website!

Let x = shortest side
then from "The hypotenuse of a right triangle is twice as long as the shortest side" we now know:
2x = hypotenuse
.
Additionally, the problem gives us the third side as  10sqrt(3)
.
Finally, pulling it all together AND applying Pythagorean theorem we get:
"(shortest side)^2" + "(third side)^2" = hypothenuse^2
 x^2 + (2x)^2 = (10sqrt(3))^2
 x^2 + 4x^2 = 100(3)
 5x^2 = 300
 x^2 = 60
 x = sqrt(60)
 x = sqrt(2*2*15)
 x = 2sqrt(15)
.
We said (from above) that the hypotenuse was 2x
hypotenuse = 2x =  2(2sqrt(15)) =  4sqrt(15) cm
or, in decimal:
hypotenuse = 15.492 cm