Question

Como fazer essa conta x2-x-12=0

Answer 1

$x^{2}$-x-12=0
x=1+/-√1+48 /2
x=1+/-√49 /2
x=1+/-7 /2
x=1+7/2=8/2=4
x=1-7/2=-6/2=-3

Answer 2

x² - x - 12 = 0

a = 1; b = - 1; c = - 12

Δ = b²  - 4ac
Δ = (-1)² - 4.1.(-12)
Δ = 1 + 48
Δ = 49

x = - b +/- √Δ = - (-1) +/- √49
           2a                 2.1

x' = 1 + 7 = 8/2 = 4
         2

x" = 1 - 7 = - 6/2 = - 3
        2