Question

Find X: tangent, cosine or sine?

Answer 1

Answer:

x ≈ 2.76

Step-by-step explanation:

Using the tangent ratio in the right triangle

tan78° = $\frac{opposite}{adjacent}$ = $\frac{AB}{BC}$ = $\frac{13}{x}$ ( multiply both sides by x )

x × tan78° = 13 ( divide both sides by tan78° )

x = $\frac{13}{tan78}$ ≈ 2.76 ( to 2 dec. places )