Two adjacent angles on a straight line are in the ratio 5:4 Find the measure of each one of these angles.
100°, 80°
Explanation:
EOF is a straight line and its adjacent angles are ∠EOB and ∠FOB.
Let ∠EOB = 5a, and ∠FOB = 4a
∠EOB + ∠FOB = 180° (EOF is a straight line)
⇒5a + 4a = 180°
⇒9a = 180°
⇒ a = 20°
Therefore, ∠EOB = 5a
= 5 × 20° = 100°
And ∠FOB = 4a
= 4 × 20° = 80°