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If $z=x+iy$, what is the modulus $|z|$? ![](https://qallery.app/diagrams/v2_337fce5574f0/img-003.jpeg)

Diagram for this question
A$x+y$
B$\sqrt{x^2+y^2}$
C$x^2+y^2$
D$\sqrt{x^2-y^2}$
Answer & Solution
Correct answer: B. $\sqrt{x^2+y^2}$
For $z=x+iy$, the modulus is the distance of the point $(x,y)$ from the origin in the Argand plane. Hence $|z|=\sqrt{x^2+y^2}$. ![](https://qallery.app/diagrams/v2_337fce5574f0/img-003.jpeg)
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