Question 317558
Hello, 
For this one, we'll use A^2+B^2=C^2 (C will be the the ladder, 5 ft) Now plug in the values we have to get: 
3^2+B^2=5^2 Rewritten as:
9+B^2=25 Subtract 9 from both sides to get:
B^2=16 Square root both sides to get:
B=4 feet high where the ladder touches the wall. 
Make sense?
RJ
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