Question

Solve the equation= 3x[cubed]+18x[squared]-21x=0

Answer 1

factor out the GCF in this case 3x

Answer 2

so like 3x[x(squared)+6x-7]=0?

Answer 3

yes then use product sum or double bubble, whatever you call it on the last part the x^2+6x-7=0

Answer 4

okay, i understand that but nowi have an x that is squared and one thats not so theyre not like values, meaning i can not combine them, so what do i do?

Answer 5

you leave the 3x separate here look at this
3x^3+18x^2-21=0
3x(x^2+6x-7)=0
3x(x+7)(x-1)=0
3x=0 x=0
x+7=0 x=-7
x-1=0 x=1
x={-7,0,1}

Answer 6

ohhh i see! so i can have more than one answer for x, thats allowed?

Answer 7

heres a trick, whatever the highest exponent in the equation is, equals the number of values you can have
example: x^4+x^2=0 has four different values for x

Answer 8

in this equation the highest is x^3 so you have three values

Answer 9

thank you!

Answer 10

no problem =)