Question

determine a raiz da equacao -x2+7x-10=0

Answer 1

-x2+7x-10=0
d = 7^2 - 4*(-1)*(-10)
d = 49 - 40
d = 9

x = -7+3/-2
x = -4/-2 = 2

x = -7-3/-2
x = -10/-2 = 5

S = {2, 5}

Answer 2

$-x^2+7x-10=0 \\ a = -1, b = 7, c = -10 \\ \\ \Delta = b^2 - 4ac \\ \Delta = 7^2 - 4\times (-1) \times (-10) \\ \Delta = 49 - 40 \\ \Delta = 9 \\ \\ x = \frac{-b \pm \sqrt{\Delta} }{2a} \\ x = \frac{-7 \pm \sqrt{9} }{2 \times (-1)} \\ x = \frac{-7 \pm 3}{-2} \\ \\ x_1 = \frac{-7 + 3}{-2} \\ x_1 = \frac{-4}{-2} = 2 \\ \\ x_2 = \frac{-7 -3}{-2} \\ x_2 = \frac{-10}{-2} = 5$

x = 2, x = 5