Question

The value of the expression $\frac{-5+10i}{3+4i}$

• A. $1-2i$
• B. $1+2i$
• C. $2-i$
• D. $2+i$

Answer 1

The correct option is B $1+2i$

Let $z=\frac{-5+10i}{3+4i}=\frac{(-5+10i)(3-4i)}{(-3+4i)(3-4i)}$
(After Rationaliztion)
$=\frac{-15+20i+30i+40}{9+16}$
$=\frac{25+50i}{25}=1+2i$