Re: In the figure above, STVW is a square. SX and YZ intersect a
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07 May 2020, 21:45
We know that STVW is a square, thus all angles must be 90.
Consider triangle UVW, we're given that UW is twice as long as UV. In case of 30-60-90 triangle only the hypotenous is twice the length of smaller side. Thus, angle VWU must be 30.
Thus, 3a = 60, a = 20. We can see that YZ passes through a and b.
Thus a+30+90+b = 180, 20+30+90+b = 180, b = 180-140, b=40. Thus, option B.