Question

How many roots does y=x2-6x+9 have

Answer 1

One root ; x = 3

Explanation:

( a ± b )² = a² ± 2ab + b²

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y = x² - 6x + 9

x² - 6x + 9 = x² - 2(x)(3) + 3² = ( x - 3 )²

( x - 3 )² = 0 ⇒ x - 3 = 0 ⇒ x = 3