Answer:
m∠1=80°, m∠2=35°, m∠3=33°
Explanation:
we know that
The sum of the interior angles of a triangle must be equal to 180 degrees
step 1
Find the measure of angle 1
In the triangle that contain the interior angle 1
∠1+69°+31°=180°
∠1+100°=180°
∠1=180°-100°=80°
step 2
Find the measure of angle 2
In the small triangle that contain the interior angle 2
∠2+45°+(180°-∠1)=180°
substitute the value of angle 1
∠2+45°+(180°-80°)=180°
∠2+45°+(100°)=180°
∠2+145°=180°
∠2=180°-145°=35°
step 3
Find the measure of angle 3
In the larger triangle that contain the interior angle 3
(∠3+31°)+69°+47°=180°
∠3+147°=180°
∠3=180°-147°=33°