Question

Find the roots of the quadratic equation if they exist by Completely the square x² - 9 = 5x

Answer 1

I think the ..Ans is (5±√61)/2 .......

Answer 2

Answer:

x = ( 5± √61 )/2

Step-by-step explanation:

Given Quadratic equation,

x² - 9 = 5x

=> x² - 5x = 9

=> x² - 2 .x . ( 5/2 ) = 9

=> x² - 2.x.( 5/2 ) + ( 5/2 )² = 9+(5/2)²

=> ( x - 5/2 )² = 9 + 25/4

=> ( x - 5/2 )² = ( 36 + 25 )/4

=> ( x - 5/2 )² = 61/4

=> x - 5/2 = ± √(61/4)

=> x = 5/2 ± √61/2

=> x = ( 5 ± √61 )/2

Therefore,

x = (5 + √61 )/2 or

x = ( 5 -√61 )/2

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