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5 times a number is 6 less than the square of that number

1 Answer

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Answer:

5x = x^2 - 6

Explanation:

a number can be represented by x,

5 times a number can be represented as the product of 5 and x, 6 less than the square of that number tells us that this is equal to a number squared minus 6. is tells us that these two expressions are equal.

If you want a working number, just solve by completing the square once this is in standard form. This is then converted to vertex form.

x^2-5x-6 = (x-5/2)^2-49/4 = (x^2-5x+25/4) -49/4 = x^2-5x-6.

(x-5/2)^2-49/4=0

(x-5/2)^2=49/4

(x-5/2) = ±√49/4

(x-5/2) = ±7/2

x=5/2±7/2

x=(5±7)/2

x=12/2,-2/2

x=6,-1

Thus, the number can either be 6 or -1.

User Markko Paas
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