Answer:

Step-by-step explanation:
Since
and
are equal, we can set them equal to each other:

Substitute
to solve for
:

The given complex number is ⇒ z = a + b i
The absolute value of z = √( a² + b² ) = 3.28
So, we will check which of the options will give 3.28
<span>( A) IF ⇒⇒ a=1.5 and b=1.7
</span>
<span>∴ √( a² + b² ) = √( 1.5² + 1.7²) = √5.14 ≈ 2.27
</span>
===================================
<span>(B) IF ⇒⇒ a=1.5 and b=3.3
</span>
<span>∴ √( a² + b² ) = √(1.5² + 3.3²) = √13.14 ≈ 3.62
</span>
====================================
<span>(C) IF ⇒⇒ a=1.7 and b=2.8
</span>
<span>∴ √( a² + b² ) = √(1.7² + 2.8²) = √10.73 ≈ 3.28
</span>
====================================
<span>(D) IF ⇒⇒ a=2.8 and b=3.3
</span>
∴ √( a² + b² ) = √(2.8² + 3.3²) = √18.73 ≈ 4.33
=====================================
So, the correct answer is option (C) <span>a=1.7,b=2.8</span>
Answer:
Step-by-step explanation:
- x + y + z = -3 --> (1)
- 3y - z = 4 --> (2)
- 2x - y - 2z = -5 --> (3)
<u>Add up (1) and (2)</u>
- x + 3y + y + z - z = -3 + 4 ⇒ x + 4y = 1 --> (4)
<u>Double (2) and subtract from (3)</u>
- 2x - y - 2z - 2(3y - z) = -5 - 2(4) ⇒ 2x - y - 2z - 6y + 2z = -5 - 8
- 2x - 7y = -13 --> (5)
<u>Double (4) and subtract (5)</u>
- 2(x + 4y) - 2x + 7y = 2 + 13 ⇒ 2x + 8y - 2x + 7y = 15 ⇒ 15y = 15 ⇒ y = 1
<u>Finding x</u>
- x + 4(1) = 1 ⇒ x = 1 - 4 ⇒ x = -3
<u>Finding z</u>
<u>So the answer is: </u>