Answer:
20° , 60° , 100°
Step-by-step explanation:
the sum of the 3 angles in a triangle is 180°
sum the parts of the ratio , 1 + 3 + 5 = 9 parts
divide 180° by 9 to find the value of one part of the ratio
180° ÷ 9 = 20° ← value of 1 part of the ratio, then
3 parts = 3 × 20° = 60°
5 parts = 5 × 20° = 100°
The measures of the 3 angles are 20° , 60° , 100°
