Question

Find the side in of point a to point c

Answer 1

Step 1:

Calculate the measure of angle ∠ABC

`\angle DBC+\angle ABC=180(\text{ sum of angles on a straight line)}`
`\angle ABC=65^0`
`\begin{gathered} \angle DBC+\angle ABC=180 \\ \angle DBC+65^0=180^0 \\ \angle DBC=180^0-65^0 \\ \angle DBC=115^0 \end{gathered}`

From the triangle in the question,

Step 2:

Calculate the value of AB using the cosine rule below

`b^2=a^2+c^2-2* a* c*\cos B`

By substituting the values, we will have

Hence,

The distance of point A to point C is = 21.26km