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Solve 2x2 − 8x = −7.

negative 2 plus or minus square root of 2
negative 2 plus or minus 2 square root of 2
quantity of 2 plus or minus square root of 2 all over 2
2 plus or minus square root of 2 end root over 2

User Interrupt
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\sf 2x^2 - 8x = - 7 \\ \\ Subtract \ -7 \ from \ both \ sides \ of \ the \ equation. \\ \\ 2x^2 - 8x - (-7 ) = - 7 - (-7) \\ \\ 2x^2 - 8x + 7 = 0 \\ \\ Use \ quadratic \ formula \ a = 2, b = -8, c = 7 \\ \\ x = (- b \pm √(b^2- 4ac) )/(2a) \\ \\ \\ x = (-(-8) \pm √((-8)^2 - 4 (2) (7) ) )/(2(2)) \\ \\ x = (8 \pm √(8) )/(4) \\ \\ x = 2 + (1)/(2)√(2) \ or \ x = 2 + (-1)/(2) √(2)

Ur answer is the fourth one 



User Vrac
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