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3 votes
when three times a number which is positive is subtracted from the square of that number the answer is 28.find the number??​

User Shephali
by
6.8k points

1 Answer

2 votes

Answer:

1.94

Explanation:

Let the number be x

So when three times a number which is positive which means when a number is x so three times a number must be 3x is subtracted from the square of that number ,

now the number 3x is subtracted from its own square i guess it should look like this


(3x)^2-3x

and the answer is 28 so the final form of the problem should be


(3x)^2-3x=28


9x^(2) -3x-28=0

now we solve the quadratic equation by using the quadratic formula and we two values for x

one is a positive value and the other is negative value we take the positive value as said in the question itself "when three times a number which is positive" so that value of x is 1.94

User Gunnar
by
6.5k points
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