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Задача Задача №2648483
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Аноним
20 января 2025 10:57 · публичный вопрос
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Аноним

25x²+20x+4=(x-7)²

Ответ нейросети
20 января 2025 10:57

To solve the equation \( 25x^2 + 20x + 4 = (x - 7)^2 \), let's first expand the right side of the equation.

  1. Expand \( (x - 7)^2 \): \[ (x - 7)^2 = x^2 - 14x + 49 \]

  2. Now, substitute this back into the equation: \[ 25x^2 + 20x + 4 = x^2 - 14x + 49 \]

  3. Next, move all terms to one side of the equation to set it to zero: \[ 25x^2 + 20x + 4 - x^2 + 14x - 49 = 0 \]

  4. Combine like terms: \[ (25x^2 - x^2) + (20x + 14x) + (4 - 49) = 0 \] \[ 24x^2 + 34x - 45 = 0 \]

  5. Now, we can simplify the equation: \[ 12x^2 + 17x - \frac{45}{2} = 0 \] (Or you can keep it as \( 24x^2 + 34x - 45 = 0 \) if you prefer not to use fractions.)

  6. To solve the quadratic equation, we can apply the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] where \(a = 24\), \(b = 34\), and \(c = -45\).

  7. Calculate the discriminant: \[ b^2 - 4ac = 34^2 - 4 \cdot 24 \cdot (-45) = 1156 + 4320 = 5476 \]

  8. Now calculate the value of \(x\): \[ x = \frac{-34 \pm \sqrt{5476}}{2 \cdot 24} \] \[ \sqrt{5476} = 74 \] \[ x = \frac{-34 \pm 74}{48} \]

  9. This gives us two possible solutions: \[ x_1 = \frac{-34 + 74}{48} = \frac{40}{48} = \frac{5}{6} \] \[ x_2 = \frac{-34 - 74}{48} = \frac{-108}{48} = -\frac{9}{4} \]

So the solutions to the equation \( 25x^2 + 20x + 4 = (x - 7)^2 \) are \( x = \frac{5}{6} \) and \( x = -\frac{9}{4} \).