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ch4aika [34]
3 years ago
12

Please help me solve this for 15 points! -x2 + 4x - 54 = 0​

Mathematics
2 answers:
Mazyrski [523]3 years ago
7 0

Answer:

x1 =2-5i*sqrt(2)

x2 =2+5i*sqrt(2)

Step-by-step explanation:

-x^2 +4x-54=0 (quadratic equation)

a=-1, b=4, c=-54

x1=(-b+sqrt(b^2-4ac))/2a

x1=(-4+sqrt(4^2 - 4*(-1)(-54))/2*(-1)

x1=(-4+sqrt(16-216))/(-2)

x1 =(-4+sqrt(-200))/(-2)

x1 =(-4+sqrt(200i^2))/(-2) i^2=-1

x1 =(-4+sqrt(100*2*i^2))/(-2)

x1 =(-4+10i*sqrt(2))/(-2)

x1 =2-5i*sqrt(2)

x2 =(-b-sqrt(b^2-4ac))/2a

x2 =(-4-10i*sqrt(2))/(-2)

x2 =2+5i*sqrt(2)

Zepler [3.9K]3 years ago
3 0
As a result, 2x = 54 so x = 27. Hope this help:)
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Let's understand the solution in detail.

Explanation:

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