In the isosceles trapezoid ABCD, draw two perpendiculars AM and BL from A and B to the side CD.
Now, LM = BA = 5 m
CD = CL + LM + MD
= CL + 5 + CL (CL = MD)
= 2CL + 5
But, CD = 11
Therefore, 2CL + 5 = 11
2CL = 11 - 5
= 6
CL = 6/2 = 3m
MD = 3m
Now, consider the right triangle AMD.
We have,
![AM^(2) = AD^(2) - MD^(2)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/g1a77svh5yosrpkoc56fu3le5el67razfl.png)
=
![4^(2) - 3^(2)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/i2docryat0gat8tbn8vuflj70z6ajzn92b.png)
= 16 - 9
= 7
Hence, height of the isosceles trapezoid = AM =
![√(7) m](https://img.qammunity.org/2019/formulas/mathematics/middle-school/zbjf2ogl3s5ihh0g0gm90tkhm2h6ro30mh.png)