InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
Find the values of V and ‘y’ in each of the following figures. |
|
Answer» a) From the figure, ∠A = 40°, ∠B = 60°, ∠D = 45° Exterior angle at C = x° Exterior angle at E = y° Exterior angle of a triangle is equal to the sum of its opposite interior angles. Exterior angle at C = ∠A + ∠B x = 40° + 60° ∴ x = 100° Exterior angle at E = ∠C + ∠D y = x + 45° y = 100° + 45° ∴ y = 145° b) From the figure, ∠M = y, ∠N = 70° Exterior angle at M = x° Exterior angle at L = 120° Exterior angle of a triangle is equal to the sum of its opposite interior angles. Exterior angle at L = ∠M + ∠N = 120° ⇒ y + 70° = 120° ⇒ y + 70 – 70 = 120 – 70 ∴ y = 50° ∠QLN + ∠MLN = 180° (linear pair of angles) 120° + ∠MLN = 180° 120° + ∠MLN – 120° = 180°- 120° ∠MLN = 60° ∴ ∠L = 60° Exterior angle at M = ∠L + ∠N x = 60° + 70° = 130° ∴ x = 130° ∴ x = 130° and y = 50° |
|