Answer:
Explanation:
(A) It is given that triangle JKL and JMN are similar, the using the basic proportionality theorem, we get
![(JK)/(JM)=(JL)/(JN)](https://img.qammunity.org/2020/formulas/mathematics/high-school/zb2jqjkrz4g7c5t6z9q6qytbp1on7swerq.png)
⇒
![(4)/(4+y-2)=(8)/(20)](https://img.qammunity.org/2020/formulas/mathematics/high-school/1sbjlmwm0vr1k8ewypu73ovv64v9j1d7ea.png)
⇒
![(4)/(y+2)=(8)/(20)](https://img.qammunity.org/2020/formulas/mathematics/high-school/muuzrtpn6a8eds05szal73x3qppuwanvq5.png)
⇒
![10=2+y](https://img.qammunity.org/2020/formulas/mathematics/high-school/myx5lu305s2u46257xrwhkhbrg2qplzrin.png)
⇒
![y=8](https://img.qammunity.org/2020/formulas/mathematics/middle-school/df4p6eserpksm1tcn9644g3i3rlflyg03l.png)
Since, triangle JKL and JMN are similar, we get
![(KL)/(KM)=(JL)/(JN)](https://img.qammunity.org/2020/formulas/mathematics/high-school/kr26ivqjj6zote3vxtu5yshidc8jsto52y.png)
⇒
![(x)/(30)=(8)/(20)](https://img.qammunity.org/2020/formulas/mathematics/high-school/dc89vgcxatybjllc29g9zj4wmkblscmmwt.png)
⇒
![x=\frac{8{*}30}{20}](https://img.qammunity.org/2020/formulas/mathematics/high-school/h6w55t5rkav8nyfcosg8zo1o6refwwaj08.png)
⇒
![x=12](https://img.qammunity.org/2020/formulas/mathematics/high-school/l1rya1wlm4u6xxftxrhbufsqe6qjhgea2l.png)
(B) a. AB is parallel to DE as when she heads from point A to point D, she takes a turn in right angle way and then again she heads to point E by taking a right angle turn, which shows that she is following the same path, thus AB is parallel to DE.
b. Since, AB is parallel to DE, therefore, ∠CAB=∠CED (Alternate angles) and ∠ACB=∠ECD (Vertically opposite angles).
c. Since, ΔABC is similar to ΔCDE, using basic proportionality theorem,
![(AB)/(CD)=(CB)/(DE)](https://img.qammunity.org/2020/formulas/mathematics/high-school/vg2ie3il7c4xpgxtgzdwazpgkurh4v0oq3.png)
⇒
![(4)/(6)=(3)/(x)](https://img.qammunity.org/2020/formulas/mathematics/high-school/d8mt8522nhjcsjt6c2bie2togcdanx7mnf.png)
⇒
![x=\frac{3{*}6}{4}](https://img.qammunity.org/2020/formulas/mathematics/high-school/efk17lv5518jwvf96akpjg7wkjqns8aoay.png)
⇒
![x=(9)/(2)m](https://img.qammunity.org/2020/formulas/mathematics/high-school/g4pwz07n2hoozm6lcs28ur1scpj735zevl.png)
Thus, DE=
![(9)/(2)m](https://img.qammunity.org/2020/formulas/mathematics/high-school/nk2d7zqvo0nwyp3xmo6ttr1tx83mgsv73z.png)