Question 1062518
.
Apply the Pythagorean theorem:


|SR| = {{{sqrt(75^2 + 40^2)}}} ft.


On Pythagorean theorem see the lessons

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Pythagorean-theorem/The-Pythagorean-Theorem.lesson>The Pythagorean Theorem</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Pythagorean-theorem/More-proofs-of-the-Pythagorean-Theorem.lesson>More proofs of the Pythagorean Theorem</A>

in this site.



You have this free of charge online textbook on Geometry

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/Triangles/GEOMETRY-your-online-textbook.lesson>GEOMETRY - YOUR ONLINE TEXTBOOK</A>

in this site. 


The referred lessons are the part of this textbook in the section "<U>Introductory Geometry problems</U>" 
under the topic "<U>Properties of triangles</U>".