The given expression is
[tex]z^2=46[/tex]We can look for a number in which square power is 46 or close to 46.
Notice that, 6 times 6 is 36, and 7 times 7 is 49. This means The number is between 6 and 7.
[tex]z\approx6,-6[/tex]Now, we use a calculator to find the exact solution.
[tex]z=\sqrt[]{46}\approx\pm6.78[/tex]