Which choice answer is it?

Mathematics

1 answer:

mafiozo [28]3 years ago

5 0

Answer:

x = 5/2 + sqrt(41)/2 or x = 5/2 - sqrt(41)/2 thus 2 is the Answer

Step-by-step explanation:

Solve for x:

x^2 - 5 x - 4 = 0

Add 4 to both sides:

x^2 - 5 x = 4

Add 25/4 to both sides:

x^2 - 5 x + 25/4 = 41/4

Write the left hand side as a square:

(x - 5/2)^2 = 41/4

Take the square root of both sides:

x - 5/2 = sqrt(41)/2 or x - 5/2 = -sqrt(41)/2

Add 5/2 to both sides:

x = 5/2 + sqrt(41)/2 or x - 5/2 = -sqrt(41)/2

Add 5/2 to both sides:

Answer: x = 5/2 + sqrt(41)/2 or x = 5/2 - sqrt(41)/2

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