Given the triangle below, what is m 2A, rounded to the nearest tenth? B
18
11
309
A
C
Triangle not drawn to scale
A. 17.8
OB. 20.4
O C. 24.2
D. 26.8

9514 1404 393

  A.  17.8°

Step-by-step explanation:

We have an angle and an opposite side, so we can use the law of sines to find the angle of interest.

  sin(A)/a = sin(C)/c

  A = arcsin(a/c·sin(C)) = arcsin(11/18·1/2) = arcsin(11/36)

  A ≈ 17.7916° ≈ 17.8°

false

step-by-step explanation:

false.   two legs of the trapezoid would be congruent, but the other two would not.   were all the legs congruent, then we'd have a square; were the 2 shorter sides congruent and the 2 longer sides also congruent, we'd have a rectangle.