SOLUTION: (2-3i)-(4-5i)+(-3+2i)

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Question 400985: (2-3i)-(4-5i)+(-3+2i)
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
(2-3i) - (4-5i) + (-3+2i)
For many reasons it is a good idea to change any subtractions to additions of the opposite:
  • Addition is easier than subtraction.
  • Addition is Commutative so the order can be changed in any desired way.
  • Addition is Associative so the grouping can be changed in any desired way.
  • Most "forms" are written in terms of addition:
    • Slope-intercept form (of the equation of a line): y = mx + b
    • Standard form (of the euqation of a line): Ax + By = C
    • Complex numbers: a + bi
    • Quadratic equations: ax%5E2+%2B+bx+%2B+c+=+0
    • etc.

Rewriting the subtractions as additions of the opposite we get:
(2+(-3i)) - (4+(-5i)) + (-3+2i)
(2+(-3i)) + (-4+5i)) + (-3+2i)
Only like terms can be added. So we will rearrange the order and the grouping so that all the like terms are grouped:
(2+(-4)+(-3)) + (-3i+5i+2i)
Adding we get:
-5 + 4i
And we are finished.