![\bold{\huge{\pink{\underline{ Solutions}}}}](https://img.qammunity.org/2023/formulas/mathematics/high-school/oems2ecv4nz0pk2wyz8avf90a7nv8asm88.png)
Answer 18 :-
We have,
Rhombus RAMS and Angle SMA = 100°
- In rhombus, The diagonals bisect each other at an angle of 90° .
Therefore,
![\sf{\angle{ AMR = 1/2}}{\sf{\angle{ SMS}}}](https://img.qammunity.org/2023/formulas/mathematics/high-school/6p5w1ouagvw7sj0pocmr9sxtivxzkt75fk.png)
![\sf{\angle{ AMR = 1/2 × 100 }}](https://img.qammunity.org/2023/formulas/mathematics/high-school/kndwgdcuuuzvbvh9o1g0aipgsypxl9w7ew.png)
![\sf{\angle{ AMR = 50° }}](https://img.qammunity.org/2023/formulas/mathematics/high-school/viie3iup79q8cm41y0h4jf1k4rcgwjajod.png)
Thus, Angle AMR is 50°
Hence, Option D is correct
Answer 19 :-
We know that,
- The sides of rhombus are equal and parallel to each other
![\sf{\angle{ AMR = }}{\sf{\angle{ RMS}}}](https://img.qammunity.org/2023/formulas/mathematics/high-school/46bqhy5d80o0p6de2rmdyanibfkqmxe7sm.png)
[ Alternative interior angles ]
![\sf{\angle{ RMS = 50° }}](https://img.qammunity.org/2023/formulas/mathematics/high-school/57jrig0au4yaw3zwxd0ihs0lw1ixckj6xz.png)
Thus, The value of Angle RMS is 50°
Hence, Option B is correct
Answer 20 :-
Here, we have to find the value of mAngleMSA
In ΔCMS,
By using Angle sum property
![\sf{ 50° +}{\sf{\angle{MSC + 90° = 180° }}}](https://img.qammunity.org/2023/formulas/mathematics/high-school/yb8zgey74sbls9r0qpokz4oqrxa2rac3wt.png)
![\sf{\angle {MSC = 180° - 140°}}](https://img.qammunity.org/2023/formulas/mathematics/high-school/3vacyp1j26cnofebf88xjgwtn1eufwrh7g.png)
![\sf{\angle{MSC = 40° }}](https://img.qammunity.org/2023/formulas/mathematics/high-school/7ro3bzyw2enzhv1gksxt43esrxjm3jifky.png)
Therefore,
![\sf{m}{\sf{\angle{MSA = 40° }}}](https://img.qammunity.org/2023/formulas/mathematics/high-school/ppa2msnzyldtthp66oak6jmxb1n00wr4k0.png)
Thus, The value of mAngle MSA is 40°