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The product of a number and 6 less than the number is 27. find the number

User Janese
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2 Answers

1 vote

Answer: The answer could be 9 or -3.

Step-by-step explanation: The product(multiply) of a number(x) and 6 less than a number(x-6) is 27.

x(x-6)=27

x^2-6x-27=0

(x-9) (x+3)=0

x=9 or x=-3

The number is 9 or -3.

User Hertzsprung
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8.0k points
5 votes

Answer:

Let's call the unknown number "x". According to the problem, we know that:

x * (x - 6) = 27

Expanding the left side of the equation, we get:

x^2 - 6x = 27

Subtracting 27 from both sides, we get:

x^2 - 6x - 27 = 0

Now we can use the quadratic formula to solve for x:

x = (-b ± sqrt(b^2 - 4ac)) / 2a

In this case, a = 1, b = -6, and c = -27, so:

x = (-(-6) ± sqrt((-6)^2 - 4(1)(-27))) / 2(1)

x = (6 ± sqrt(180)) / 2

x = (6 ± 6sqrt(5)) / 2

x = 3 ± 3sqrt(5)

So the two possible solutions are:

x = 3 + 3sqrt(5) ≈ 8.746

x = 3 - 3sqrt(5) ≈ -2.746

Since the problem statement doesn't specify whether the number should be positive or not, both solutions are valid.

User Tukan
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8.8k points

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