Find the missing length. Round to the nearest tenth, if necessary.

A right triangle has legs measuring 8 units and x units and a hypotenuse measuring 21 units.

3 answers

General Idea:

By using the Pythagorean theorem which states that in a right triangle the sum of square of two legs is equal to the square of hypotenuse. We can find the length of the third side.

Given:

We can see shortest side a is 4 inches, hypotenuse is c is 8 inches and middle side is 4√3. This is quality of a special triangle. The smallest side (a) is opposite the smallest angle (30°), the middle side (b) is opposite the angle (60°) and the longest side (c) is opposite the largest angle (90°).

The triangle 30°-60° - 90° triangle will be of the ratio 1:√3:2.

Conclusion:

The length of the other leg is 4√3 in
The measures of the acute angles are : 30° and 60°
Oops wrong problem
x^2 + 8^2 = 21^2
x^2 + 64 = 441
x^2 = 377
x = sqrt(377) = appr 19.42