How do you find the roots, real and imaginary, of $y= -2x^2 + 5x + 72$ using the quadratic formula?

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Answer 1 · 2018-05-12T03:12:52

$color(maroon)("Two roots are " x = (5 + sqrt(601)) / 4, (5 - sqrt(601)) / 4$

$"Quadratic Formula " x = (-b +- sqrt(b^2 - 4ac)) / (2a)$

$"Given " y = -2x^2 + 5x + 72$

$= -2, b = 5, c = 72$

$x = (-5 +- sqrt(25 + (4 * 2 * 72))) / (2 * -2)$

$x = (-5 +- sqrt(601)) / -4$

$color(maroon)(x = (5 +- sqrt(601)) / 4$

How do you find the roots, real and imaginary, of y= -2x^2 + 5x + 72 y= -2x^2 + 5x + 72 using the quadratic formula?