The ratio of three angles of a triangle is 4 : 7 : 9. What is the measure of the greatest angle?
Answer & explanation
Correct answer: option 2
Sum of all three angles of a triangle = 180°
⇒ 4x + 7x + 9x = 180°
⇒ 20x = 180°
⇒ x = 9°
⇒ The greatest angle = 9x = 81°