A safe slope for a ladder is 1 ft of run for every 4 ft of rise. Vincent needs to use ladder to reach a window sill that is 22 ft above the ground. How far from the house should the base of the ladder be?

1 Answer
Dec 30, 2016

#5color(white)(.)"feet "6color(white)(.)"inches"#

Explanation:

This is a case of Similar Triangles so we could use ratio

#("up")/("along") -> 4/1 = 22/("along")#

To change 4 into 22 multiply by #22/4#. However what we do to the top we do to the bottom. For multiply and divide that is.

So we have: #" "(4xx22/4)/(1xx22/4) = (color(white)(.)22color(white)(.))/(22/4)#

#("up")/("along") =(color(white)(.)22color(white)(.))/(22/4)#

#"along "=22/4 = 5 1/2 feet#

#5color(white)(.)"feet "6color(white)(.)"inches"#