Answer:
3+4+5=12
180°(sum of all angles of triangle)÷12(sum of the the given ratio)=15°
15×3=45°
15×4=60°
15×5=75°
=180°
The measure of each angle are 45°,60° and 75°
Step-by-step explanation:
We know that the sum of the triangle's angles are 180.Use the Partitive Proportion Method