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Grade 11Algebra

Let the complex number Z satisfy the equation
z + |z| = 1 +7i then the value of |z|^2 is?

Profile image of Chirag Arora
8 Years agoGrade 11
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4 Answers

Profile image of Naga sree harsha reddy
8 Years ago
Let z=x+it,then |z|=√x^2+y^2=1; compare real terms i.e;x+√x^2+y^2=1; and compare imaginary part with imaginary part i.e;y=7 put in 1 and get value of x as |z| is required;find √x^2+y^2
Profile image of aravind m t
8 Years ago
real partpart of is 24..we will get by solving =625....|z|^2 √a^2+7^2 +a=1;hence 
Profile image of aravind m t
8 Years ago
real partpart of is 24..we will get by solving |z|^2 √a^2+7^2 +a=1....;hence|z|^2 =625
Profile image of Samyak Jain
8 Years ago
z + |z| = 1 +7i                   ….......... (1)
Let z = x + iy  \therefore  |z| = \sqrt{}(x+ y2) 
(1) can be rewritten as x + iy + \sqrt{}x+ y = 1 + 7i
Equate real and imaginary parts of LHS & RHS.
\therefore y = 7 ;  x + \sqrt{}(x+ y2) = 1  or  x + \sqrt{}(x+ 49) = 1
x+ 49 = (1 – x)2  i.e.  x+ 49 = 1 – 2x + x2
49 = 1 – 2x  
2x = – 48   or    x = – 24
\therefore |z| = \sqrt{}(x+ y2)    =  \sqrt{}(– 24)+ 72  
        = \sqrt{}576 + 49   =  \sqrt{}625
   |z|  =  25