Answer:
BC ≈ 14 units
Explanation:
using Pythagoras' identity in the right triangle.
the square on the hypotenuse is equal to the sum of the squares on the other 2 sides , that is
BC² + AB² = AC²
BC² + 18² = 23²
BC² + 324 = 529 ( subtract 324 from both sides )
BC² = 205 ( take square root of both sides )
BC =
= 14.317.. ≈ 14 units ( to the nearest unit )