Question 1155635
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The sum of interior angles of ANY triangle is 180°.  Therefore,


    (x+9) + (7x+3) + 4x = 180   degrees,


     12x  + 12          = 180

     12x                = 180 - 12 = 168

       x                           = 168/12 = 14.


<U>ANSWER</U>.  m < R = 12+ 9 = 21 degrees;  m < S = 7*12+3 = 87 degrees;  m < T = 4*12 = 48 dehrees.
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Solved.


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<U>Note</U>.


<pre>
    Make blank space separator before and after the symbol  " < "  - otherwise, your formula will be UNREADABLE.

    Wright the formulas related to angles as you see them in my post.
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