Question

What is the value of X

Answer 1

x ≈ 23.31

Explanation:

We can use the law of cosines because we know 2 sides and 1 angle.

The general formula for the law of cosines if the triangle sides are a, b,c and α is the angle between sides a and b. c is the missing side.

`c = \sqrt{a^(2) +b^(2) -2*a*b* cos \alpha }`

In our problem the law of cosines is

x =
`\sqrt{21^(2) +13^(2) - 2*21*13 *cos 83}`

x ≈ 23.31