How do you find the roots, real and imaginary, of $y=-5(x-2)^2+3x^2-15$ using the quadratic formula?

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Answer 1 · 2018-06-09T08:46:03

$color(violet)(x = 5 + sqrt 15, 5 - sqrt15$

$y = -5(x-2)^2 + 3x^2 - 15$

$y = -5x^2 + 20x - 20 + 3x^2 - 15$

$y = -2x^2 + 20x - 35$

$x = (-20 +- sqrt(20^2 - 280)) / -4$

$x = (-20 +- sqrt120) / -4$

$color(violet)(x = 5 + sqrt 15, 5 - sqrt15$

How do you find the roots, real and imaginary, of y=-5(x-2)^2+3x^2-15 y=-5(x-2)^2+3x^2-15 using the quadratic formula?