18. [-/4.54 Points] DETAILS SMITHPOW10 5.3.058. Assume that the given angles have been measured, and calculate the angle (marked as x) that could not be found by direct measurement. (Assume a = 550 and the angle between the ground and the wall forms a right angle.) X= Submit Answer 19. [-/4.54 Points] DETAILS SMITHPOW10 5.3.060. The legs of a picnic table form a triangle in which AC and BC have the same length, as shown in the figure below. Find the measures of angles x and y so that the top of the table will be parallel to the ground. (Assume mcACB = 100.) X= X Submit Answer 20. [-/4.54 Points] DETAILS SMITHPOW10 5.4.048. Use similar triangles and a proportion to find the length of the lake shown in the figure. 50.0 ft 210 ft * 140 ft Submit