Modulus of a Complex Number

A complex number is a number of the form a + bi, where a and b are real numbers and i is the imaginary unit, defined as i = sqrt(-1).

Consider the complex number 3 + 4i.

To find the modulus of this complex number, use the formula: $$|z| = ext{sqrt}(a^2 + b^2)$$, where z is the complex number a + bi.

Calculate the modulus of 3 + 4i and enter your answer in the grid-in format.