Question

h) -x²+6x-5=0
i) 6x²+x-1=0

Answer 1

h) -x²+6x-5=0
Δ = b² -4ac
Δ = 6² -4*(-1)*(-5)
Δ = 36 -20
Δ = 16

x1 = -b + √Δ/2*a
x1 = -6 + √16/2*(-1) 
x1 = -6 + 4/-2
x1 = -2/-2
x1 = 1

x2 = -b - √Δ/2*a
x2 = -6 - 4/-2
x2 = -10/-2
x2 = 5
S = {1,5}

i) 6x²+x-1=0
Δ = 1² - 4*6*(-1)
Δ = 1 + 24
Δ = 25
x1 = -1 + √25/12
x1 = -1 +5/12
x1 = 4/12
x1 = 1/3

x2 = -1 - √25/12
x2 = -1 -5/12
x2 = -6/12
x2 = -1/2

S = {-1/2, 1/3}