Question

Find the length of side AB. Give your answer to 1 decimal place.

Answer 1

Answer:

Length of side AB = 5.6 cm

Step-by-step explanation:

From the figure attached.

In right triangle ABC,

m∠ABC = 62°

m(BC) = 12 cm

By applying Cosine rule in this triangle,

Cos62° = $\frac{\text{Adjacent side}}{\text{Hypotenuse}}$

Cos62°= $\frac{AB}{BC}$

0.46947 = $\frac{AB}{12}$

AB = 12 × 0.46947

AB = 5.63

     ≈ 5.6 cm  

Therefore, length of side AB = 5.6 cm