Задача Задача №2623572
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To solve the quadratic equation \(9x^2 - 7x - 2 = 0\), we can use the quadratic formula:
\[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \]
Here, \(a = 9\), \(b = -7\), and \(c = -2\).
- Calculate \(b^2 - 4ac\):
\[ b^2 - 4ac = (-7)^2 - 4(9)(-2) = 49 + 72 = 121 \]
- Since \(121\) is a perfect square, we take the square root:
\[ \sqrt{121} = 11 \]
- Now substitute back into the quadratic formula:
\[ x = \frac{-(-7) \pm 11}{2(9)} = \frac{7 \pm 11}{18} \]
- Calculate the two possible values for \(x\):
- For \(x_1\):
[ x_1 = \frac{7 + 11}{18} = \frac{