A billiards triangle is equiangular. What is the perimeter? base = 4x- 9 1/4 side = 2x+1 A triangular shaped trellis has angles R, S, and T that measure 73Â°, 73Â°, and 34Â°, respectively. If ST = 4y + 6 and TR = 7y - 21, what is the value of y? -5 -15 -9 -11 Two triangular tiles each have two sides... show more A billiards triangle is equiangular. What is the perimeter? base = 4x- 9 1/4 side = 2x+1 A triangular shaped trellis has angles R, S, and T that measure 73Â°, 73Â°, and 34Â°, respectively. If ST = 4y + 6 and TR = 7y - 21, what is the value of y? -5 -15 -9 -11 Two triangular tiles each have two sides measuring 4 inches.