Question

Confused on my math work

Answer 1

The right answer is the third option, 24,04 cm.

Explanation:

Let's add an altitude FH.

Then, DH = HE =
`(a)/(2)` = 17.

`FH^2=DH*HE \\ FH = √(17*17) \\ FH = 17`

FH = DH = HE = 17.

`EF^2 = FH^2+HE^2\\ EF = √(289+289) \\ EF = √(578)`

`√(578) = 24,0416... = 24,04.`