If (x + yi) + (2(x + yi) + 3i) = 9, what is x + yi? A. 3 − i B. -3 + i C. -3 − i D. 3 + i E. 9 − 3i
Accepted Solution
A:
Answer:A. [tex]3-i[/tex]Step-by-step explanation:Given the complex number expression;[tex](x+yi)+(2(x+yi)+3i)=9[/tex]Expand:[tex](x+yi)+2(x+yi)+3i=9[/tex]Group similar expressions;[tex](x+yi)+2(x+yi)=9-3i[/tex]Simplify[tex]3(x+yi)=9-3i[/tex]Solve for [tex](x+yi)[/tex];[tex]3(x+yi)=3(3-i)[/tex]Divide through by 3;[tex](x+yi)=3-i[/tex]