Posted by cedric mitz on .
A 20 foot ladder is leaning against a building.if the ratio of the base of ladder's distance from the building to its top's height from the ground is 3:4,find how high the top of the ladder is from the ground.

maths 
Reiny,
since ratio of the two other sides is 3:4
let their lengths be 3x and 4x
(3x)^2 + (4x)^2 = 20^2
9x^2 + 16x^2 = 400
x^2 = 16
x = 4
so the two sides are ......
and .....
take if from above.