One Knot Problem - Find two unknown masses

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Homework Statement



See the attachment.
We're asked to find the masses of M1 and M2. I'm wondering how this is possible, 'cause there's two variables and only one known? Do I have to use sine/cosine law?

m3 = 0.1998 kg
T3 = (0.1998 kg)(-9.80 m/s^2) = -1.96 N

Vertical angle A (between T3 and T1) = 38.0 degrees
Vertical angle B (between T3 and T2) = 27.0 degrees

Homework Equations



F = ma
F = ma sin (Θ)

The Attempt at a Solution



I tried to solve with algebra:

m1 g sin (A) + m2 g sin (B) = m3 g

Gravity cancels.

m1 sin (A) + m2 sin (B) = m3 g

...And that's about as far as I got :(

Any help/hints would be appreciated muchly.. the Physics head decided we should only get two days to do our labs.. it's due tomorrow.
 

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Hint: Force is a vector...it will have both horizontal and vertical components, and both must be zero for the mass m3 not to move...
 
Yeah, I got it now. Had to:

Solve for m1 in the equation for the sum of all the x components and the equation for the sum of all the y components.

Then make them equal to each other, solve definitively for m2, then substitute to solve for m1.

Thanks for the help!
 
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