Question

решите уравнение
$y ^{2} - 3y - 5 = 0$
$5x ^{2} - 11x + 2 = 0$
$9y ^{2} - 30y + 25= 0$
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Answer 1

y² - 3y - 5 = 0

D = 9 + 20 = 29

y12 = (3 +- √29)/2

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5x² - 11x + 2 = 0

D = 121 - 40 = 81

x12=(11 +- 9)/10 = 2   1/5

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9y² - 30y + 25 = 0

(3y)² - 2*5*3y + 5² = 0

(3y - 5)² = 0

y = 5/3