Question

9. The ratio of the interior angle measures of a triangle is 1 : 4 : 5. What are the angle measures

Answer 1

18° , 72° , 90°

Explanation:

sum the parts of the ratio , 1 + 4 + 5 = 10 parts

the sum of the 3 angles in a triangle is 180°

divide 180° by 10 to find the value of one part of the ratio

180° ÷ 10 = 18° ← value of 1 part of the ratio, then

4 parts = 4 × 18° = 72°

5 parts = 5 × 18° = 90°

the measures of the angles are then 18° , 72° , 90°

Answer 2

Answer: 90, 72, 18

Explanation:

1x + 4x + 5x = 180 (All the angles in a triangle add up to 180 degrees)

10x = 180

x = 18

1 x 18 = 18

4 x 18 = 72

5 x 18 = 90

90 + 72+ 18 = 180

Hope this helps ✌️