Question

x2-x-20=0 ajuda equação 2 grau

Answer 1

x² - x - 20 = 0
a=1
b= -1
c= -20
Δ=b²-4ac
Δ= (-1)² -4.(1).(-20)
Δ= 1 + 80
Δ= 81

x = -b+-√Δ/2a
x = -(-1)+-√81/2.1
x = 1+-9/2
x1 = 1+9/2 = 10/2= 5
x2 = 1-9/2 = -8/2 = -4

V= {5,-4}