X + (7 - 3i) + (5 + 9i) + 13i = 10 - 5i
Subtract 13i from both sides
x + (7 -3i) + (5 + 9i) = 10 - 18i
Subtract (5 + 9i). MAKE SURE YOU SUBTRACT 9i TOO. In other words, distribute the negative and subtract 5 and 9i at the same time.
x + (7 - 3i) = 5 - 27i
Do the same with (7 - 3i). You'll be adding 3i since -(-3i) = 3i.
x = -2 - 24i
Answer:
First image attached
The error was done in Step E, because student did not multiply 
by the negative sign in numerator. Step E must be 
.
Second image attached
The error was done in Step C, because the student omitted the 
of the algebraic identity 
. Step C must be 
Step-by-step explanation:
First image attached
The error was done in Step E, because student did not multiply by the negative sign in numerator. The real numerator in Step E should be:
Hence, Step E must be .
Second image attached
The error was done in Step C, because the student omitted the of the algebraic identity . Step C must be
And further steps are described below:
Step D
Which according to the Quadratic Formula, represents a polynomial with complex roots. That is: (
, 
, 
)
(Conjugated complex roots)
Step E
Step F
Answer:
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Answer::: greater than 1.645
