Math  Real number system
posted by CheezyReezy .
Solve the following equation in the real number system. Please show all of your work.
x^4 + 6x^3 + x^2  24x  20 = 0
Help!!!!

Let f(x)=x^4+6x^3+x^224x20
Real roots are looking for among
+1,+2,+4,+5,+10,+20
f(1)=16+1+2420=0
Divide f(x) by (x+1):
f(x)=(x+1)(x^3+5x^24x20)
Let g(x)=x^3+5x^24x20
g(5)=125+125+2020=0
Divide g(x) by (x+5):
g(x)=(x+5)(x^24)
f(x)=(x+1)(x+5)(x+2)(x2) 
what is 2/5 in the real number system