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Math Help - a+bi=0 only when a=0 and b=0 right?

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    a+bi=0 only when a=0 and b=0 right?

    a+bi=0 only when a=0 and b=0 right?

    I was doing an SAT math level 1 problem that started with:

    y=7-x+(x+2)i

    so I changed it to:

    0 = 7-x-y + (x+2)i

    So b=0 --> x=-2 --> y=9 , right?
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    Re: a+bi=0 only when a=0 and b=0 right?

    Quote Originally Posted by lamp23 View Post
    a+bi=0 only when a=0 and b=0 right?
    Yes.

    Quote Originally Posted by lamp23 View Post
    I was doing an SAT math level 1 problem that started with:

    y=7-x+(x+2)i

    so I changed it to:

    0 = 7-x-y + (x+2)i

    So b=0 --> x=-2 --> y=9 , right?
    Yes. The real and imaginary parts must be equal so you solve the equations x+2=0 \text{  and  } 7-x-y=0 which is what you did in your head
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