Answer:
AC = 5
Explanation:
AC is the diagonal of the rectangle ABCD and splits the rectangle into 2 right triangles.
Using right triangle ABC with hypotenuse AC
Applying Pythagoras' theorem gives
AC² = AB² + BC² ← substitute given values
AC² = 4² + 3² = 16 + 9 = 25
Take the square root of both sides
AC =
= 5