Given:
M is the mid-point of RS
N is the mid-point of ST
MN = 18.4
To find:
The length of RT.
Solution:
The reference image is attached below.
Joining mid-point M and N, we get mid-segment MN.
MN is parallel to RT.
Triangle mid-segment theorem:
If a segments joins the mid point of a two sides of triangle, then the segment is parallel to the third side and is half of that side.
![$\Rightarrow MN=(1)/(2) RT](https://img.qammunity.org/2021/formulas/mathematics/middle-school/x9u6bks0g0zrl98lk2y4lvlioe0vw5mbfw.png)
Substitute MN = 18.4
![$\Rightarrow 18.4 =(1)/(2) RT](https://img.qammunity.org/2021/formulas/mathematics/middle-school/s7hi7ysdoyz610qbvsbb3ohw3w2ka7a6kh.png)
Multiply by 2 on both sides.
![$\Rightarrow 2* 18.4 =2* (1)/(2) RT](https://img.qammunity.org/2021/formulas/mathematics/middle-school/y75luk8iura45vck4ak8vav0bhmxprhsla.png)
![$\Rightarrow 36.8=RT](https://img.qammunity.org/2021/formulas/mathematics/middle-school/uaq8nwu2j7l2538gmid4y5qh2oq264rvn0.png)
The length of RT is 36.8.