

Get live Maths 1-on-1 Classs - Class 6 to 12
Ex 5.1
Ex 5.1, 1 (ii) Important
Ex 5.1, 1 (iii) Important
Ex 5.1, 2 (i)
Ex 5.1, 2 (ii) Important
Ex 5.1, 2 (iii) Important
Ex 5.1, 3 (i)
Ex 5.1, 3 (ii) Important
Ex 5.1, 3 (iii)
Ex 5.1, 3 (iv) Important
Ex 5.1, 3 (v)
Ex 5.1, 3 (vi) Important
Ex 5.1, 4
Ex 5.1, 5 Important
Ex 5.1, 6
Ex 5.1, 7 Important
Ex 5.1, 8 You are here
Ex 5.1, 9
Ex 5.1, 10 Important
Ex 5.1, 11
Ex 5.1, 12 (i)
Ex 5.1, 12 (ii) Important
Ex 5.1, 13 (i) Important
Ex 5.1, 13 (ii)
Ex 5.1, 13 (iii) Important
Ex 5.1, 13 (iv)
Ex 5.1, 13 (v)
Ex 5.1, 13 (vi) Important
Ex 5.1, 14
Last updated at March 16, 2023 by Teachoo
Ex 5.1, 8 (Method 1) An angle is greater than 45°. Is its complementary angle greater than 45° or equal to 45° or less than 45°? Let’s assume angle is 𝜃 where 𝜃 > 45° We know that, If two angles are complementary, their sum is 90° Angle 1 + Angle 2 = 90° 𝜃 + Angle 2 = 90° Angle 2 = 90° − 𝜃 Now, 𝜃 > 45° Multiplying by –1 both sides −𝜃 < −45° Adding 90° both sides 90° − 𝜃 < 90° − 45° 90° − 𝜃 < 45° Angle 2 < 45° ∴ The complementary angle would be less than 45° Ex 5.1, 8 (Method 2) An angle is greater than 45°. Is its complementary angle greater than 45° or equal to 45° or less than 45°? We know that, If two angles are complementary, their sum is 90° Let two angles be ∠1 and ∠2. Where ∠ 1 is greater than 45°, we need to find ∠ 2 Let’s take some examples Example 1: Suppose ∠ 1 and ∠ 2 are complementary. If ∠1 = 60°, ∠2 = ? ∠1 + ∠2 = 90° 60° + ∠2 = 90° ∠2 = 90° − 60° ∠2 = 30° Example 2: Suppose ∠ 1 and ∠ 2 are complementary. If ∠ 1 = 46°, ∠ 2 = ? ∠1 + ∠2 = 90° 46° + ∠2 = 90° ∠2 = 90° − 46° ∠2 = 44° Thus, If one of the complementary angle is greater than 45°, the other one will be less than 45°