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Lostsunrise [7]
2 years ago
13

5. Solve the equation z^2 + 4z - 9 = 0 by completing the square.

Mathematics
1 answer:
Luba_88 [7]2 years ago
8 0

Answer:

A. Z = 2 + N13

Step-by-step explanation:

Let's solve your equation step-by-step.

0=z2+4z−9

Step 1: Subtract z^2+4z-9 from both sides.

0−(z2+4z−9)=z2+4z−9−(z2+4z−9)

−z2−4z+9=0

For this equation: a=-1, b=-4, c=9

−1z2+−4z+9=0

Step 2: Use quadratic formula with a=-1, b=-4, c=9.

z=

−b±√b2−4ac

2a

z=

−(−4)±√(−4)2−4(−1)(9)

2(−1)

z=

4±√52

−2

z=−2−√13 or z=−2+√13

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Where ^ stands for raised to power.
Let
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By Pythagoras rule
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3 years ago
Hey can you help me fast!!!
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6 0
2 years ago
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Is x-3/5 = N and N = 6, what is the value of x?
scZoUnD [109]

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Step-by-step explanation:

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