1234
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The Quadratic Formula

Here's another one:

2x^2 - 12x + 13 = 0

a = 2 , b = -12 , c = 13

x = -b +/- sqrt( b^2 - 4ac ) / 2a = - ( -12 ) +/- sqrt( ( -12 )^2 - 4 ( 2 ) ( 13 ) ) / ( 2 ( 2 ) ) = 12 +/- sqrt( 144 - 104 ) / 4 = 12 +/- sqrt( 40 ) / 4

exact: { ( 12 - sqrt( 40 ) / 4 ) , ( 12 + sqrt( 40 ) / 4 ) }

decimal approximation: { 1.419 , 4.581 }

YOUR TURN:

Solve  x^2 + 7x + 2 = 0