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Use completing the square to solve for x in the equation (x+ 7)(x-9)=25,
OX= 4 or 6
O X-2 or 14
O x=1V89
O x=1 V87

Use Completing The Square To Solve For X In The Equation X 7x925 OX 4 Or 6 O X2 Or 14 O X1V89 O X1 V87 class=

Answer :

Answer:

3rd option

Step-by-step explanation:

(x + 7)(x - 9) = 25 ← expand left side using FOIL

x² - 2x - 63 = 25 ( add 63 to both sides )

x² - 2x = 88

To complete the square

add ( half the coefficient of the x- term )² to both sides

x² + 2(- 1)x + 1 = 88 + 1

(x - 1)² = 89 ( take square root of both sides )

x - 1 = ± [tex]\sqrt{89}[/tex] ( add 1 to both sides )

x = 1 ± [tex]\sqrt{89}[/tex]

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