А²-9=(а-3)²
(а-3)(а+3)=(а+3)²
а-3=а+3
<span>b</span>₁ = <span>х - 1
b</span>₂ = <span>3х - 5
b</span>₃ = <span>9х - 19
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b</span>₃ : b₂ = b₂ : b₁<span>
(9х - 19)/(3х-5) = (3х-5)/(х-1)
(9x-19)(x-1) = (3x-5)</span>²
<span>9x</span>² - 9x - 19x + 19 = 9x² - 30x + 25
<span>9x</span>² - 28x + 19 - 9x² + 30x - 25 = 0
<span>2x - 6 = 0
2x = 6
x = 3
Ответ: при х=3
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Пожалуйста. надеюсь понятно
<span><span>![(2a-3)^{2}-4a(a+1)=4a^{2}-12a+9-4a^{2}-4a=(4a^{2}-4a^{2})+(-12a-4a)+9=-16a+9=9-16a](https://tex.z-dn.net/?f=%282a-3%29%5E%7B2%7D-4a%28a%2B1%29%3D4a%5E%7B2%7D-12a%2B9-4a%5E%7B2%7D-4a%3D%284a%5E%7B2%7D-4a%5E%7B2%7D%29%2B%28-12a-4a%29%2B9%3D-16a%2B9%3D9-16a)
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