Question

Help plsFind xa(21)b(27)c(9)d(18)​

Answer 1

9514 1404 393

Answer:

  a.  21

Step-by-step explanation:

The external part of the hypotenuse of the right triangle is shown. The full length of the hypotenuse is 9+20 = 29. The Pythagorean theorem can be used to find x.

  x^2 +20^2 = 29^2

  x^2 = 841 -400

  x = √441

  x = 21

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Alternate solution

The diameter of the circle is 2·20 = 40 units, so the product of distances from the external vertex to the opposite sides of the circle along the secant is (9)(40+9). The product of the distances along the tangent is x·x. These two products are equal, so ...

  x^2 = 9(49)

  x = (√9)(√49) = 3·7

  x = 21