Respuesta :

Answer:

[tex]xy=-109i[/tex]

[tex]\frac{x}{y}=\frac{60}{109}+\frac{91}{109}i[/tex]

Step-by-step explanation:

[tex]xy=(10-3i)(3-10i)[/tex]

To compute x times y must use foil on the right hand side.

First:  [tex]10(3)=30[/tex]

Outer: [tex]10(-10i)=-100i[/tex]

Inner: [tex]-3i(3)=-9i[/tex]

Last: [tex]-3i(-10i)=30i^2=-30[/tex]

------------------------------------Add like terms:

[tex]-109i[/tex]

----------------

[tex]\frac{x}{y}[/tex]

[tex]\frac{10-3i}{3-10i}[/tex]

Multiply top and bottom by bottom's conjugate:

[tex]\frac{(10-3i)(3+10i)}{(3-10i)(3+10i)}[/tex]

Foil the top and just do first and last of Foil for the bottom since the bottom contains multiplying conjugates:

[tex]\frac{30+100i-9i-30i^2}{9-100i^2}[/tex]

Replace [tex]i^2[/tex] with -1:

[tex]\frac{30+91i+30}{9+100}[/tex]

[tex]\frac{60+91i}{109}[/tex]

[tex]\frac{60}{109}+\frac{91}{109}i[/tex]