Answer
$|z|=1$
see graph below
.
Work Step by Step
See p. 602, Graphing Complex Numbers
The complex plane is determined by the real axis and the imaginary axis.
To graph the complex number a + bi, we plot the ordered pair of numbers (a,b) in this plane
See p. 603,
The modulus (or absolute value) of the complex number $z=a+bi$ is
$|z|=\sqrt{a^{2}+b^{2}}$
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Write z in the form a+bi:
$z=\displaystyle \frac{3}{5}+\frac{4}{5}i$
Plot $(a,b)=(\displaystyle \frac{3}{5},\frac{4}{5})$ in the complex plane
(see image).
$|z|=\sqrt{(\frac{3}{5})^{2}+(\frac{4}{5})^{2}}=\sqrt{\frac{9+16}{25}}=1$