Answer:

Explanation:
Let the height of the largest triangle marked be
. We can set up the following equation:
(if you're unfamiliar with trig, this is likely introduced to you as 30-60-90 triangle rules)
This height is also a leg of a 45-45-90 triangle, as marked in the diagram. From the isosceles-base-theorem, the other leg of this triangle must also be equal to
. Therefore, we can use the Pythagorean theorem to solve for
:
(you can also use trig or 45-45-90 triangle rules which are derived from the Pythagorean theorem)
Segment
consists of two shorter segments, a left segment and a right segment. We've already found that the left segment is equal to 17. To find the right segment we can use trig, the Pythagorean theorem, or 30-60-90 triangle rules (derived from the Pythagorean theorem):
Using Pythagorean Theorem:

Therefore, we have:
