3x^7 = 81x^4
divided both sides by 3
x^7 = 27x^4
divided both sides by x^4
x^3 = 27
take the cube root of each side
x=3
Find the real-number solution of the equation. 3x^7 = 81x^4
I got this far...
3x^7 - 81x^4 = 0
x^4 (3x^3 - 81) = 0
2 answers
or
x = 0
since ....
x&7 - 27x^4 = 0
x^4 (x^3 - 27) = 0
x^4 = 0 or x^3 = 27
x = 0 or x = 3
x = 0
since ....
x&7 - 27x^4 = 0
x^4 (x^3 - 27) = 0
x^4 = 0 or x^3 = 27
x = 0 or x = 3