SOLUTION: How do you find the modulus of z= 3/(5+7i) ? I am asked to find the modulus and Arg(z), but I cannot figure out what x & y are for |z|=sqrt(x^2+y^2) (the modulus). Thanks!

Algebra ->  Complex Numbers Imaginary Numbers Solvers and Lesson -> SOLUTION: How do you find the modulus of z= 3/(5+7i) ? I am asked to find the modulus and Arg(z), but I cannot figure out what x & y are for |z|=sqrt(x^2+y^2) (the modulus). Thanks!      Log On


   

Question 265623: How do you find the modulus of z= 3/(5+7i) ? I am asked to find the modulus and Arg(z), but I cannot figure out what x & y are for |z|=sqrt(x^2+y^2) (the modulus).
Thanks!
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
How do you find the modulus of z= 3/(5+7i) ? I am asked to find the modulus and Arg(z), but I cannot figure out what x & y are for |z|=sqrt(x^2+y^2) (the modulus).
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z = 3/(5+7i)
z = 3(5-7i)/74
modulus = 3*sqrt(74)/74
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Arg(z) = arctan(-7/5) =~ 125.54 degs