Question

How do you use the Pythagorean Theorem to find the missing side of the triangle given: b = 5, c = 8?

Answer 1

If 8 is the hypotenuse than side `a=sqrt(39)`

If 8 is not the hypotenuse than sude `a=sqrt(89)`

Explanation:

You have not declared if the triangle is a right triangle ( has a 90 degree angle) nor have you declared if the side c is the hypotenuse or not. However, by including the use of Pythagoras you have implied it is a right triangle.

Let the unknown side be labeled `a`

`color(blue)("Assumption 1: It is a right triangle and 8 is the hypotenuse")`

`=>a^2=8^2-5^2" " =" " 64-25" "=" "39`

`a=sqrt(39)`

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`color(blue)("Assumption 2: It is a right triangle and 8 is not the hypotenuse")`

`->a^2=8^2+5^2 =89`

`=>a=sqrt(89)`