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?

Question

3191 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-12-30T14:43:59

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

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: $" "(4xx22/4)/(1xx22/4) = (color(white)(.)22color(white)(.))/(22/4)$

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

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

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