Answer:
RS = 2
Step-by-step explanation:
Using Pythagoras' identity in the right triangle
RS² + RT² = TS² , that is
RS² + 6² = 8²
RS² + 36 = 64 ( subtract 36 from both sides )
RS² = 28 ( take the square root of both sides )
RS = =
= 2
≈ 5.3 ( to 1 dec. place )