Question

BC = ??
need help asap

Answer 1

5.87

Explanation:

Concepts

The three different trigonometric functions are sine, cosine, and tangent. They can be memorized as the mnemonic SOHCAHTOA, where:

• Sine = Opposite/Hypotenuse
• Cosine = Adjacent/Hypotenuse
• Tangent = Opposite/Adjacent

The hypotenuse will always stay the same, but depending on the highlighted angle, the opposite and adjacent side can change.

Application

In this case, we're asked to find the length of BC. We're given the length of the opposite side as 7 units. The adjacent side to m∠50° is BC. Since we're dealing with opposite and adjacent, we're going to be using tangent.

Solution (Calculator Needed)

• tan(50°) = 7/x
• tan(50°) * x = 7/x * x
• tan(50°)x = 7
• x = 7/tan(50°)
• x ≈ 5.87

Answer 2

BC = 5.87

Explanation:

To find the last angle:

180° - 50° - 90° = 40°

Once we know that, we can use our given side angle pair to figure out the length.

`(7)/(sin(50))` *
`(?)/(sin(40))` ->
`(7*sin(40))/(sin(50))`= ?

Then we plug into a calculator to get: 5.87