NCERT Exemplar Solutions
Class 7 - Mathematics - Unit 5: Lines And Angles - Problems and SolutionsQuestion 73
Class 7 - Mathematics - Unit 5: Lines And Angles - Problems and Solutions
Question. 73
73. In each of the following figures, write, if any, (i) each pair of vertically opposite angles, and (ii) each linear pair.
Answer:
(i) Vertically opposite: ∠1, ∠3; ∠2, ∠4; ∠5, ∠7; ∠6, ∠8
Linear pairs: ∠1, ∠2; ∠2, ∠3; ∠3, ∠4; ∠4, ∠1; ∠5, ∠6; ∠6, ∠7; ∠7, ∠8; ∠8, ∠5
(ii) Vertically opposite: none
Linear pairs: ∠ABD, ∠DBC; ∠ABE, ∠EBC
(iii) Vertically opposite: none
Linear pairs: none
(iv) Vertically opposite: ∠ROQ, ∠POS; ∠ROP, ∠QOS
Linear pairs: ∠ROP, ∠POS; ∠ROT, ∠TOS; ∠QOS, ∠SOP; ∠QOT, ∠TOP
Detailed Answer with Explanation:
Vertically opposite angles are formed when two lines intersect. Linear pairs are adjacent angles whose sum is 180°. Each case is checked carefully.