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If angle A =90 degree , b=1 cm and a =2 cm then solve the following right angled triangle ABC ​

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Answer:

  • Angle A = 90 degrees, side a = 2.
  • Angle B = 30 degrees, side b = 1.
  • Angle C = 60 degrees, side c =
    √(3).

Side c:

  • If angle A is 90 degrees, side a is the hypotenuse.

  • c^(2) + b^(2) = a^(2) <--- this is NOT the correct way to write the Pythagorean theorem. I changed it to fit the side lengths. Normally, it is
    a^(2) + b^(2) = c^(2), where c is the hypotenuse. Since a is the hypotenuse, I switched the variables.

  • c^(2) + (1)^(2) = (2)^(2)

  • c^(2) + 1 = 4

  • c^(2) = 3

  • c = √(3)

Finding the angles:

  • In a 30-60-90 right triangle, the...
  • Shortest leg = x
  • Longest leg =
    x√(3)
  • Hypotenuse = 2x
  • In this case, the shortest leg is 1, the longer leg is
    √(3) (or
    1*√(3)), and the hypotenuse is 2 (or
    2*1).
  • As a result, this is a 30-60-90 triangle -- angle B is 30 degrees while angle C is 60 degrees.
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