65 and 70

Find the area of each triangle ABC. See Example 5. 65. a = 12 m, b = 16 m, c = 25 m 66. a = 22 in., b = 45 in., c = 31 in. 67. a = 154 cm, b = 179 cm, c = 183 cm 68. a = 25.4 yd, b = 38.2 yd, c = 19.8 yd 69. a = 76.3 ft, b = 109 ft, c = 98.8 ft 70. a = 15.8 m, b = 21.7 m, c = 10.9 m