How do you evaluate $(- 1+ 6i ) + ( - 9+ 9i )$ ?

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Answer 1 · 2017-12-07T15:27:49

$color(blue)(-10+15i)$

We have an expression with two Complex numbers

$color(red)((-1+6i)+(-9+9i))$ $color(blue)(Expression.1)$

A Complex number is a combination of a Real Number and an Imaginary Number.

Complex numbers have a standard form: $color(red)a+$ $color(blue)(bi)$

Where $color(red)a$ is the Real Part and $color(blue)(bi)$ is the Imaginary Part.

The question involves adding two Complex Numbers in $color(blue)(Expression.1)$

We must now group the Real Part and the Imaginary Part of the Complex Number.

We will use the following Complex Number formula to simplify:

$color(green)((a+bi) +- (c+di) = (a+c)+-(b+-d)i)$

Hence, we can write our $color(blue)(Expression.1)$ as

$color(blue)([(-1) + (-9) ]+[ 6 + 9 ]i)$

$color(blue)(-10+15i)$ our final answer

I hope this helps.

How do you evaluate (- 1+ 6i ) + ( - 9+ 9i )(- 1+ 6i ) + ( - 9+ 9i )?