Question

x^4-10x^2+9 = 0

x^5-29x^3+100x=0

(2x^2+3)^2-7(2x^2+3)+10=0

(x^2-16)*(x^3-1)=0

6x^3-x^2+20x+12=0

Answer 1

x^2=a
a^2-10x+9=0
D=100-36=64
a(1)=(10+6)/2=8
a(2)=(10-6)/2=2
x^2=2 x=2^1/2
x^2=8 x=8^1/2