Find the angles in a tension on 2 ropes problem

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AI Thread Summary
The problem involves a 4.50 kg block suspended by two ropes with tensions of 28.3 N and 40.5 N. To find the angles θ1 and θ2, the equations T1cosθ1 + T2cosθ2 = 0 and T1sinθ1 + T2sinθ2 = mg are used. A correction was provided to change the x-axis equation to T1cosθ1 - T2cosθ2 = 0. The discussion emphasizes isolating one tension to substitute into the other equation for solving both angles. The focus remains on correctly applying trigonometric identities and Newton's second law to find the angles.
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Homework Statement



A 4.50 kg block of gruyere cheese is suspended as shown. Rope 1 on the left has a tension of 28.3 N; rope 2 on the right has a tension of 40.5 N.
(a) What is θ1, the angle made by rope 1? (b) What is θ2? State each angle as the positive angle "inside" the triangle the ropes form.
http://i47.tinypic.com/ivy260.png

Homework Equations



Newton's second law
The problem also included these identities:
http://i47.tinypic.com/mtxv1z.png

The Attempt at a Solution



I tried to solve for one of the thetas using the equation for the x-axis
T1cosθ1+T2cosθ2 = 0

and then substitute it in the equation for the y-axis *trying* to use the trig identities
T1sinθ1+T2sinθ2 = mg

I doubt I'm doing it right but either way I'm way stuck after an hour
help!please!
 
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bkhurley said:

The Attempt at a Solution



I tried to solve for one of the thetas using the equation for the x-axis
T1cosθ1+T2cosθ2 = 0

and then substitute it in the equation for the y-axis *trying* to use the trig identities
T1sinθ1+T2sinθ2 = mg

I doubt I'm doing it right but either way I'm way stuck after an hour
help!please!

this one should be T1cosθ1-T2cosθ2 = 0

yes you are going correct, just take the equation I corrected for you and isolate either T1 or T2 and substitute into the next equation.
 
okay sounds good but I'm not solving for T I'm solving for both thetas
 
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