Question

The area on the map is represented in the shape of a triangle as shown below.
Find the measure of the unknown angle y.

• A. 55°
• B. 60°
• C. 45°
• D. 50°

Answer 1

The correct option is A 55°

According to the angle sum property of triangles, the sum of the measure of internal angles of a triangle is 180°.

$i.e.,\angle ABC+\angle BCA+\angle CAB=180°$


Here,$\angle ABC=70°$
and$\angle CAB=55°$

On substituting, we get:
$y+55°+70°=180°$

$\Rightarrow y=180°-(55°+70°)$

$\Rightarrow y=180°-125°$

$\Rightarrow y=55°$

So, the measure of ∠BCA is 55°.