Answer:
3,21
Step-by-step explanation:
[tex](4,2)^{2} = (2,7)^{2} + z^{2} \\1764 * 10^{-2} = 729 * 10^{-2} + z^{2}\\z^{2} = 1035 * 10^{-2}\\z = 3\sqrt{115} * 10^{-1}\\[/tex]
z ≅ 3 * 10,7 * [tex]10^{-1}[/tex]≅ 3,21
