Question

Calculo da equação
X²-3x-10=0

Answer 1

Δ = (-3)² - 4 . ( 1) . (-10)
Δ = 49

X' = (3 + 7)/2 = 5
X' = (3 - 7)/2 = -2

X = 5; X = -2;

Answer 2

x = +3 +/-√(-3)² - 4·1·(-10)/2·1
x = 3 +/- √9+40/2
x = 3 +/- 7/2 

x' = 3+7/2   -> x' = 5
x" = 3-7/2  ->  x" = -2

S = {-2, 5}