Question

Given that x = 5.7 m and θ = 43°, work out BC rounded to 3 SF​

Answer 1

Answer:

BC ≈ 4.17

Step-by-step explanation:

Using the cosine ratio in the right triangle

cos43° = $\frac{adjacent}{hypotenuse}$ = $\frac{BC}{AC}$ = $\frac{BC}{5.7}$ ( multiply both sides by 5.7 )

5.7 × cos43° = BC , then

BC ≈ 4.17 ( to 3 sf )

Answer 2

Use SOH CAH TOA
label sides hypotenuse, adjacent
cos43 = adjacent / hypotenuse

BC/AC = BC/5.7

x both sides by 5.7

5.7 x cos43 =BC

BC = 4.17(3sf)