What horizontal distance can a painter climbing a ladder before it slips

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This is for an online homework assignment that apparently is not crediting the proper answer. I'm just curious to know if I got this right or if I'm way off. Thanks in advance.

Homework Statement


If the coefficient of static friction is 0.362, and the same ladder makes a 61.0° angle with respect to the horizontal, how far along the length of the ladder can a 70.2-kg painter climb before the ladder begins to slip?

Homework Equations


[tex]\mu[/tex]s = [tex]\frac{P}{N}[/tex]
P = force of wall on ladder
N = weight of ladder + painter

dx = [P(dy)sin[tex]\theta[/tex]a]/(Nsin[tex]\theta[/tex]b)

theta a = the angle between the ladder and the floor
theta b = the angle between the ladder and the wall

The Attempt at a Solution



Force of wall on ladder

P = 0.362(743.66) = 268.84N

Horizontal distance of painter

dx = [268.84(10.6)sin 61]/[(743.66)sin 29] = 6.91 m
 
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Thank you! I've been poking around here and there. I've almost posted a couple of other questions, but in the process of trying to input the problem on here, I've solved the problem. I attached a FBD I drew up.
 

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