If the sum of a number and its square is 156, what is the number?a)16b...
Let the number be x.
x+x2=156
x2+x−156=0
(x−12)(x+13)=0
x+13=0
x=−13 (Since x is a natural number)
x−12=0
x=12
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If the sum of a number and its square is 156, what is the number?a)16b...
The condition is x^2 + X = 156.
So initially we need to take the closest square to 156 and it should be smaller than 156.
The required number is 144 = 12^2 . Add 12 to 144 and the sum comes out to be 156.
Hence x=12
If the sum of a number and its square is 156, what is the number?a)16b...
Explanation:
Let the number be x. According to the problem, we have:
x + x^2 = 156
or, x^2 + x - 156 = 0
This is a quadratic equation. We can solve it using the quadratic formula:
x = (-b ± √(b^2 - 4ac)) / 2a
where a, b, and c are the coefficients of the quadratic equation (ax^2 + bx + c = 0).
In this case, a = 1, b = 1, and c = -156. Substituting these values in the quadratic formula, we get:
x = (-1 ± √(1^2 - 4*1*(-156))) / 2*1
Simplifying this expression, we get:
x = (-1 ± √625) / 2
Therefore, the solutions of the quadratic equation are:
x1 = (-1 + √625) / 2 = 12
x2 = (-1 - √625) / 2 = -13
Since x represents a number, we reject the negative solution and choose x = 12 as the answer.
Therefore, the correct option is (c) 12.