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Does anyone has Algebra ll and if so can you please help me with this problem 5i/-2-6i And also I can't pay you but I hope God can give more good luck

1 Answer

3 votes

Answer:


s = (5i)/(-2-6i) = -(30)/(40)-(10)/(40)i

Explanation:

We have the following complex number
s = (5i)/(-2-6i), we proceed to simplify the expression as follows:

1)
(5i)/(-2-6i) Given.

2)
(5i)\cdot (-2-6i)^(-1) Definition of division.

3)
[(5i)\cdot (-2-6i)^(-1)]\cdot [(-2+6i)\cdot (-2+6i)^(-1)] Modulative and associative properties/Existence of the additive inverser

4)
[(5i)\cdot (-2+6i)]\cdot [(-2-6i)^(-1)\cdot (-2+6i)^(-1)] Commutative and associative properties.

5)
[(5i)\cdot (-2+6i)]\cdot [(-2-6i)\cdot (-2+6i)]^(-1)
a^(c)\cdot b^(c) = (a\cdot b)^(c)

6)
[(5i)\cdot (-2+6i)]\cdot [4+36]^(-1)
(a+b)\cdot (a-b) = a^(2)-b^(2)/Definition of complex number/
a\cdot (-b) = -a\cdot b

7)
[(5i)\cdot (-2)+(5i)\cdot (6i)]\cdot 40^(-1) Definition of sum.

8)
(-10\cdot i+30\cdot i^(2))\cdot 40^(-1)
a\cdot (-b) = -a\cdot b/Associative and commutative properties.

9)
(-30-10i)\cdot 40^(-1) Commutative properties/Definition of complex number/
a\cdot (-b) = -a\cdot b

10)
-30\cdot 40^(-1)-(10i)\cdot 40^(-1) Distributive property.

11)
-(30)/(40)-(10)/(40)i Definition of division/Result.


s = (5i)/(-2-6i) = -(30)/(40)-(10)/(40)i

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